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Massimo Zerani - One of the best experts on this subject based on the ideXlab platform.
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pituitary adenylate cyclase activating polypeptide induces testicular testosterone synthesis through pge2 mediation in crested newt Triturus Carnifex
Journal of Experimental Zoology, 2002Co-Authors: Anna Gobbetti, Massimo ZeraniAbstract:The aim of the present work was to study the possible role of adenylate cyclase-activating polypeptide (PACAP) 38 in the testicular intracellular mechanism regulating steroidogenesis of crested newt, Triturus Carnifex. Gonads were incubated in vitro with PACAP 38 and prostaglandin (PG) E(2) alone or with inhibitors of cyclooxygenase (COX), adenylate cyclase (AC), and phospholipase C (PLC) for 30 min and 60 min. PGE(2), PGF(2 alpha), testosterone, and estradiol-17 beta were measured in the culture medium; aromatase (AR) activity and cAMP were assessed in the tissue. PACAP 38 increased PGE(2) (30 min and 60 min), estradiol-17 beta (60 min), cAMP (60 min), and AR (60 min) but decreased testosterone (60 min). PGE(2) increased estradiol-17 beta, cAMP, and AR and decreased testosterone at 30 and 60 min.PLC inhibitor counteracted the effects of PACAP 38, while AC inhibitor counteracted these effects except for PGE(2) increase. AC inhibitor counteracted the effects of PGE(2), while PLC did not. COX inhibitor decreased PGF(2 alpha) (30 min and 60 min), PGE(2) (30 min and 60 min), estradiol-17 beta (60 min), cAMP (60 min), and AR (60 min), but increased testosterone (60 min). These in vitro results suggest that, in newt testis, PACAP 38 acts on PLC, inducing the increase of PGE(2) which, in turn, acting on AC, increases AR activity with the consequent estradiol-17 beta increase and testosterone decrease.
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substance p downregulates basal and gonadotropin releasing hormone induced gonadotropin in vitro secretion by pituitary gland of crested newt Triturus Carnifex
Journal of Neuroendocrinology, 2001Co-Authors: Anna Gobbetti, Cristina Petrelli, Massimo ZeraniAbstract:The possible role of Substance P (SP) was studied in the modulation of basal and gonadotopin-releasing hormone (GnRH)-induced gonadotropin secretion in the urodele crested newt, Triturus Carnifex. During prereproduction, reproduction (noncourtship and courtship), refractory, recovery and aestivation, male and female pituitaries were incubated with medium-alone, GnRH, SP, GnRH receptor antagonist (antide), and SP receptor antagonist (L-703606). Since antisera raised against gonadotropins are not available for this species, we measured these hormones indirectly through their effects on the secretion of testicular androgens and ovarian progesterone from gonads superfused with the preincubated pituitaries. Pituitaries of both sexes preincubated with medium-alone, GnRH, GnRH plus L-703606, and GnRH plus SP plus L-703606 increased steroid secretion during prereproduction, noncourtship, courtship, and recovery; the increase induced by the pituitaries incubated with medium-alone was lower during prereproduction, noncourtship, and recovery. Pituitaries preincubated with SP, GnRH plus SP, GnRH plus SP plus antide, and SP plus antide did not change basal steroid secretion in any of the reproductive phases considered. Antide, L-703606, GnRH plus antide, GnRH plus SP plus antide plus L-703606, SP plus L-703606, and antide plus L-703606 experimental groups showed the same results as those with medium-alone. These results suggest that SP downregulates gonadotropin release in both Triturus Carnifex sexes. In addition, an antagonist role, through receptor-independent mechanisms, exists between GnRH (upregulation) and SP (downregulation) in the modulation of pituitary.
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In Vitro Nitric Oxide Effects on Basal and Gonadotropin-Releasing Hormone-Induced Gonadotropin Secretion by Pituitary Gland of Male Crested Newt (Triturus Carnifex) during the Annual Reproductive Cycle
Biology of reproduction, 1999Co-Authors: Anna Gobbetti, Massimo ZeraniAbstract:The objective of this study was to test the possible nitric oxide (NO) involvement in pituitary gonadotropin secretion in the male crested newt, Triturus Carnifex. Pituitaries were incubated in vitro with medium alone, GnRH, NO donor (NOd, sodium nitroprusside), NO synthase inhibitor (NOSi, Nomega-nitro-L-arginine methyl ester), cGMP analogue (cGMPa, 8-bromo-cGMP), soluble guanylate cyclase inhibitor (sGCi, cystamine), GnRH plus NOSi, GnRH plus sGCi, and NOd plus sGCi during the annual reproductive cycle: pre-reproduction, reproduction (noncourtship and courtship), and the refractory, recovery, and estivation periods. To determine pituitary gonadotropin secretion indirectly, newt testes were superfused in vitro with preincubated pituitaries, and androgen release was determined. NO synthase (NOS) activity and cGMP levels were assessed in the preincubated pituitaries. Medium alone- and GnRH-preincubated pituitary increased androgen secretion during pre-reproduction, noncourtship, courtship, and recovery; the GnRH-induced increase was higher than the medium alone-induced increase during pre-reproduction, noncourtship, and recovery. NOd and cGMPa increased androgens in all reproductive phases considered except courtship; the NOd- and cGMP-induced increase was higher than the medium alone-induced increase during pre-reproduction, noncourtship, and recovery. NOS activity was highest during courtship and lowest during the refractory and estivation periods. GnRH increased NOS activity during pre-reproduction, noncourtship, and recovery. Cyclic GMP levels were highest during courtship and lowest during the refractory period and estivation. GnRH increased cGMP levels during pre-reproduction, noncourtship, and recovery, while NOd did so during all reproductive phases considered. These results suggest that basal and GnRH-induced gonadotropin secretion are up-regulated by NO in the pituitary gland of the male Triturus Carnifex.
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presence of pituitary adenylate cyclase activating polypeptide 38 immuno like material in the brain and ovary of the female crested newt Triturus Carnifex its involvement in the ovarian synthesis of prostaglandins and steroids
Journal of Endocrinology, 1997Co-Authors: Anna Gobbetti, Massimo Zerani, Antonino Miano, Massimo Bramucci, Oretta Murri, Domenico AmiciAbstract:The presence of pituitary adenylate cyclase-activating peptide (PACAP) 38-immuno-like material (PACAP 38-IL) in the brain and ovary of the crested newt, Triturus Carnifex, and its action on ovarian steroidogenesis and prostaglandin synthesis were evaluated. The HPLC, brain and ovary extract peaks that eluted like PACAP 38 were considered PACAP 38-like material. The concentrations of PACAP 38-II in the HPLC extracts were measured by RIA. T. Carnifex ovary was incubated with PACAP 38, brain and ovary PACAP 38-IL, and inhibitors of cyclooxygenase (COX), adenylate cyclase (AC) and phospholipase C (PLC) for 30 and 60 min. PACAI 38, and brain and ovary PACAP 38-IL increased prostaglandin E2 (PGE2) (30 and 60 min), and progesterone and corticosterone (60 min), but decreased oestradiol-17 beta (60 min). COX and PLC inhibitors counteracted the increases in PGE2, progesterone and corticosterone and the decrease in oestradiol-17 beta, and the AC, inhibitor also counteracted them except for PGE2. These results suggest that PACAP 38-IL, present in T. Carnifex brain and ovary, acts on PLC, inducing the increase of PGE2 which, in turn, acting on AC, induces increases in progesterone and corticosterone and a decrease in oestradiol-17 beta.
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prostaglandin e2 9 ketoreductase and prostaglandin f2α activate brain aromatase to induce courtship in the male crested newt Triturus Carnifex
Hormones and Behavior, 1995Co-Authors: Anna Gobbetti, Massimo ZeraniAbstract:Abstract Testosterone, 17β-estradiol, prostaglandin E2 (PGE2), and prostaglandin F2α (PGF2α) were monitored in plasma and in in vitro brain incubations during the main phases of male Triturus Carnifex courtship. Plasma and in vitro results were similar: testosterone was highest in inactive males, while 17β-estradiol and PGF2α were highest and PGE2 lowest during approach. PGF2αin vitro treatments decreased testosterone and increased 17β-estradiol, while 9-ketoreductase inhibitor in vitro treatments increased testosterone and decreased estradiol. In addition, in vitro aromatase and PGE2-9-ketoreductase activities were highest during approach. PGF2αin vitro treatments increased aromatase, while 9-ketoreductase inhibitor decreased aromatase. These results suggest that 9-ketoreductase and PGF2α enhance aromatase activity to trigger male Triturus Carnifex courtship.
Anna Gobbetti - One of the best experts on this subject based on the ideXlab platform.
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pituitary adenylate cyclase activating polypeptide induces testicular testosterone synthesis through pge2 mediation in crested newt Triturus Carnifex
Journal of Experimental Zoology, 2002Co-Authors: Anna Gobbetti, Massimo ZeraniAbstract:The aim of the present work was to study the possible role of adenylate cyclase-activating polypeptide (PACAP) 38 in the testicular intracellular mechanism regulating steroidogenesis of crested newt, Triturus Carnifex. Gonads were incubated in vitro with PACAP 38 and prostaglandin (PG) E(2) alone or with inhibitors of cyclooxygenase (COX), adenylate cyclase (AC), and phospholipase C (PLC) for 30 min and 60 min. PGE(2), PGF(2 alpha), testosterone, and estradiol-17 beta were measured in the culture medium; aromatase (AR) activity and cAMP were assessed in the tissue. PACAP 38 increased PGE(2) (30 min and 60 min), estradiol-17 beta (60 min), cAMP (60 min), and AR (60 min) but decreased testosterone (60 min). PGE(2) increased estradiol-17 beta, cAMP, and AR and decreased testosterone at 30 and 60 min.PLC inhibitor counteracted the effects of PACAP 38, while AC inhibitor counteracted these effects except for PGE(2) increase. AC inhibitor counteracted the effects of PGE(2), while PLC did not. COX inhibitor decreased PGF(2 alpha) (30 min and 60 min), PGE(2) (30 min and 60 min), estradiol-17 beta (60 min), cAMP (60 min), and AR (60 min), but increased testosterone (60 min). These in vitro results suggest that, in newt testis, PACAP 38 acts on PLC, inducing the increase of PGE(2) which, in turn, acting on AC, increases AR activity with the consequent estradiol-17 beta increase and testosterone decrease.
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substance p downregulates basal and gonadotropin releasing hormone induced gonadotropin in vitro secretion by pituitary gland of crested newt Triturus Carnifex
Journal of Neuroendocrinology, 2001Co-Authors: Anna Gobbetti, Cristina Petrelli, Massimo ZeraniAbstract:The possible role of Substance P (SP) was studied in the modulation of basal and gonadotopin-releasing hormone (GnRH)-induced gonadotropin secretion in the urodele crested newt, Triturus Carnifex. During prereproduction, reproduction (noncourtship and courtship), refractory, recovery and aestivation, male and female pituitaries were incubated with medium-alone, GnRH, SP, GnRH receptor antagonist (antide), and SP receptor antagonist (L-703606). Since antisera raised against gonadotropins are not available for this species, we measured these hormones indirectly through their effects on the secretion of testicular androgens and ovarian progesterone from gonads superfused with the preincubated pituitaries. Pituitaries of both sexes preincubated with medium-alone, GnRH, GnRH plus L-703606, and GnRH plus SP plus L-703606 increased steroid secretion during prereproduction, noncourtship, courtship, and recovery; the increase induced by the pituitaries incubated with medium-alone was lower during prereproduction, noncourtship, and recovery. Pituitaries preincubated with SP, GnRH plus SP, GnRH plus SP plus antide, and SP plus antide did not change basal steroid secretion in any of the reproductive phases considered. Antide, L-703606, GnRH plus antide, GnRH plus SP plus antide plus L-703606, SP plus L-703606, and antide plus L-703606 experimental groups showed the same results as those with medium-alone. These results suggest that SP downregulates gonadotropin release in both Triturus Carnifex sexes. In addition, an antagonist role, through receptor-independent mechanisms, exists between GnRH (upregulation) and SP (downregulation) in the modulation of pituitary.
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In Vitro Nitric Oxide Effects on Basal and Gonadotropin-Releasing Hormone-Induced Gonadotropin Secretion by Pituitary Gland of Male Crested Newt (Triturus Carnifex) during the Annual Reproductive Cycle
Biology of reproduction, 1999Co-Authors: Anna Gobbetti, Massimo ZeraniAbstract:The objective of this study was to test the possible nitric oxide (NO) involvement in pituitary gonadotropin secretion in the male crested newt, Triturus Carnifex. Pituitaries were incubated in vitro with medium alone, GnRH, NO donor (NOd, sodium nitroprusside), NO synthase inhibitor (NOSi, Nomega-nitro-L-arginine methyl ester), cGMP analogue (cGMPa, 8-bromo-cGMP), soluble guanylate cyclase inhibitor (sGCi, cystamine), GnRH plus NOSi, GnRH plus sGCi, and NOd plus sGCi during the annual reproductive cycle: pre-reproduction, reproduction (noncourtship and courtship), and the refractory, recovery, and estivation periods. To determine pituitary gonadotropin secretion indirectly, newt testes were superfused in vitro with preincubated pituitaries, and androgen release was determined. NO synthase (NOS) activity and cGMP levels were assessed in the preincubated pituitaries. Medium alone- and GnRH-preincubated pituitary increased androgen secretion during pre-reproduction, noncourtship, courtship, and recovery; the GnRH-induced increase was higher than the medium alone-induced increase during pre-reproduction, noncourtship, and recovery. NOd and cGMPa increased androgens in all reproductive phases considered except courtship; the NOd- and cGMP-induced increase was higher than the medium alone-induced increase during pre-reproduction, noncourtship, and recovery. NOS activity was highest during courtship and lowest during the refractory and estivation periods. GnRH increased NOS activity during pre-reproduction, noncourtship, and recovery. Cyclic GMP levels were highest during courtship and lowest during the refractory period and estivation. GnRH increased cGMP levels during pre-reproduction, noncourtship, and recovery, while NOd did so during all reproductive phases considered. These results suggest that basal and GnRH-induced gonadotropin secretion are up-regulated by NO in the pituitary gland of the male Triturus Carnifex.
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presence of pituitary adenylate cyclase activating polypeptide 38 immuno like material in the brain and ovary of the female crested newt Triturus Carnifex its involvement in the ovarian synthesis of prostaglandins and steroids
Journal of Endocrinology, 1997Co-Authors: Anna Gobbetti, Massimo Zerani, Antonino Miano, Massimo Bramucci, Oretta Murri, Domenico AmiciAbstract:The presence of pituitary adenylate cyclase-activating peptide (PACAP) 38-immuno-like material (PACAP 38-IL) in the brain and ovary of the crested newt, Triturus Carnifex, and its action on ovarian steroidogenesis and prostaglandin synthesis were evaluated. The HPLC, brain and ovary extract peaks that eluted like PACAP 38 were considered PACAP 38-like material. The concentrations of PACAP 38-II in the HPLC extracts were measured by RIA. T. Carnifex ovary was incubated with PACAP 38, brain and ovary PACAP 38-IL, and inhibitors of cyclooxygenase (COX), adenylate cyclase (AC) and phospholipase C (PLC) for 30 and 60 min. PACAI 38, and brain and ovary PACAP 38-IL increased prostaglandin E2 (PGE2) (30 and 60 min), and progesterone and corticosterone (60 min), but decreased oestradiol-17 beta (60 min). COX and PLC inhibitors counteracted the increases in PGE2, progesterone and corticosterone and the decrease in oestradiol-17 beta, and the AC, inhibitor also counteracted them except for PGE2. These results suggest that PACAP 38-IL, present in T. Carnifex brain and ovary, acts on PLC, inducing the increase of PGE2 which, in turn, acting on AC, induces increases in progesterone and corticosterone and a decrease in oestradiol-17 beta.
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prostaglandin e2 9 ketoreductase and prostaglandin f2α activate brain aromatase to induce courtship in the male crested newt Triturus Carnifex
Hormones and Behavior, 1995Co-Authors: Anna Gobbetti, Massimo ZeraniAbstract:Abstract Testosterone, 17β-estradiol, prostaglandin E2 (PGE2), and prostaglandin F2α (PGF2α) were monitored in plasma and in in vitro brain incubations during the main phases of male Triturus Carnifex courtship. Plasma and in vitro results were similar: testosterone was highest in inactive males, while 17β-estradiol and PGF2α were highest and PGE2 lowest during approach. PGF2αin vitro treatments decreased testosterone and increased 17β-estradiol, while 9-ketoreductase inhibitor in vitro treatments increased testosterone and decreased estradiol. In addition, in vitro aromatase and PGE2-9-ketoreductase activities were highest during approach. PGF2αin vitro treatments increased aromatase, while 9-ketoreductase inhibitor decreased aromatase. These results suggest that 9-ketoreductase and PGF2α enhance aromatase activity to trigger male Triturus Carnifex courtship.
Vincenza Laforgia - One of the best experts on this subject based on the ideXlab platform.
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histological changes apoptosis and metallothionein levels in Triturus Carnifex amphibia urodela exposed to environmental cadmium concentrations
Aquatic Toxicology, 2016Co-Authors: Anna Capaldo, Ivana Caputo, Carla Esposito, Marilena Lepretti, Rosaria Scudiero, Francesca Trinchella, Anna Marabotti, Vincenza LaforgiaAbstract:Abstract The aim of this study was to verify if the freshwater safety values established from the European Community (1998) and the Italian Ministry of Health (2001) for cadmium (44.5 nM/L in drinking water and 178 nM/L in sewage waters) were safe for amphibians, since at these same concentrations cadmium induced endocrine disruption in the newt Triturus Carnifex . Adult male specimens of T. Carnifex were exposed daily to cadmium (44.5 nM/L and 178 nM/L as CdCl 2 , nominal concentrations), respectively, during 3- and 9-months; at the same time, control newts were exposed to tap water only. The accumulation of cadmium in the skin, liver and kidney, the levels of metallothioneins in the skin and the liver, the expression of metallothionein mRNA in the liver, as well as the presence of histological alterations and of apoptosis in the target organs were evaluated. The 9-months exposure induced cadmium accumulation in all the tissues examined; moreover, histological changes were observed in all the tissues examined, irrespective of the dose or the time of exposure. Apoptosis was only detected in the kidney, whereas metallothioneins and metallothionein mRNA did not increase. This study demonstrates that the existing chronic water quality criterion established for cadmium induces in the newt T. Carnifex cadmium accumulation and histological alterations in the target organs examined. Together with our previous results, showing that, at these same concentrations, cadmium induced endocrine disruption, the present results suggest that the existing chronic water quality criterion for cadmium appears to be not protective of amphibians.
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chronic exposure to cadmium disrupts the adrenal gland activity of the newt Triturus Carnifex amphibia urodela
BioMed Research International, 2013Co-Authors: Vincenza Laforgia, Ivana Caputo, Carla Esposito, Marilena Lepretti, Anna CapaldoAbstract:We intended to verify the safety of the freshwater values established for cadmium by the European Community and the Italian Ministry of Health in drinking water (5 μg/L) and sewage waters (20 μg/L). Therefore, we chronically exposed the newt Triturus Carnifex to 5 μg/L and 20 μg/L doses of cadmium, respectively, during 3 and 9 months and verified the effects on the adrenal gland. We evaluated the serum concentrations of adrenocorticotropic hormone (ACTH), corticosterone, aldosterone, norepinephrine, and epinephrine. During the 3-month exposure, both doses of cadmium decreased ACTH and corticosterone serum levels and increased aldosterone and epinephrine serum levels. During the 9-month exposure, the 5 μg/L dose decreased ACTH and increased aldosterone and epinephrine serum levels; the 20 μg/L dose decreased norepinephrine and epinephrine serum levels, without affecting the other hormones. It was concluded that (1) chronic exposure to the safety values established for cadmium disrupted the adrenal gland activity and (2) the effects of cadmium were related both to the length of exposure and the dose administered. Moreover, our results suggest probable risks to human health, due to the use of water contaminated by cadmium.
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endocrine disrupting effects of nonylphenol in the newt Triturus Carnifex amphibia urodela
Comparative Biochemistry and Physiology C-toxicology & Pharmacology, 2012Co-Authors: Anna Capaldo, Salvatore Valiante, Maria De Falco, Rosaria Sciarrillo, Massimo Maddaloni, Vincenza LaforgiaAbstract:The aim of our study was to verify whether environmental concentrations of nonylphenol influenced the adrenal gland of Triturus Carnifex. Newts were exposed to 19 μg/L nominal concentration of nonylphenol throughout the periods of December-January and March-April, corresponding to different stages of the chromaffin cell functional cycle. The morphological features of the steroidogenic and chromaffin tissues, and the serum levels of ACTH, aldosterone, corticosterone, norepinephrine and epinephrine were evaluated. Nonylphenol did not influence ACTH serum levels. During the two periods examined, the steroidogenic tissue had the same reaction: the quantity of cytoplasmic lipids, and the corticosteroid serum levels, decreased, suggesting the inhibition of synthesis and release of corticosteroids. During the two periods examined, the chromaffin tissue reacted differently to nonylphenol. During December-January, the numeric ratio of norepinephrine granules to epinephrine granules, and the epinephrine serum levels, increased, suggesting the stimulation of epinephrine release. During March-April, the numeric ratio of norepinephrine granules to epinephrine granules did not change, and the norepinephrine serum levels decreased, suggesting the inhibition of norepinephrine release. Our results show that nonylphenol influences the activity of the newt adrenal gland; considering the physiological role of this gland, our results suggest that nonylphenol may contribute to amphibian decline.
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annual and daily serum aldosterone and catecholamine patterns in males of the italian crested newt Triturus Carnifex amphibia urodela
Italian Journal of Zoology, 2010Co-Authors: Salvatore Valiante, Vincenza Laforgia, Rosaria Sciarrillo, M De Falco, Anna CapaldoAbstract:Abstract The present work studied the annual and daily aldosterone, norepinephrine and epinephrine patterns in the newt Triturus Carnifex. The annual variations of the serum aldosterone were evaluated every month by radioimmunoassay, from September to July; the daily variations of this hormone were evaluated in the months of January, April, July and November. Aldosterone levels were low from September to November (lowest value 187.23 ± 19.7 pg/ml in November), increased in December, remained high until March and peaked in April (587.25 ± 58.2 pg/ml). In May, the levels decreased and remained steady until July. Considering the daily aldosterone pattern, in all the examined months, serum aldosterone levels were lowest at 5:00 am (lowest value 162.51 ± 17.4 pg/ml in November) and peaked at 5:00 pm (maximal value 2075.00 ± 213.00 pg/ml in April). As regards the annual catecholamine pattern as measured by HPLC, serum norepinephrine levels were low from September to November (lowest value 541.13 ± 39.8 pg/ml in...
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pituitary adenylate cyclase activating polypeptide and its receptor pac1 in the testis of Triturus Carnifex and podarcis sicula
General and Comparative Endocrinology, 2010Co-Authors: Marisa Agnese, Salvatore Valiante, Vincenza Laforgia, Francesco Angelini, Piero Andreuccetti, Marina PriscoAbstract:The pituitary adenylate cyclase-activating polypeptide (PACAP) is a member of the glucagon-related family that occurs in two amidated forms with 38 (PACAP38) and 27 (PACAP27) amino acids. First discovered in the brain, it was then localized in several peripheral tissues of mammals, including the testis. However, current knowledge of the expression and function of PACAP and its receptor PAC(1) in the reproductive system of non-mammalian vertebrates, and particularly in the testis, is still limited. The aim of this work was to study the presence of PACAP and its receptor PAC(1) in the testis of two non-mammalian vertebrates during the breeding season: the crested newt Triturus Carnifex and the wall lizard Podarcis sicula. The expression and distribution of this neuropeptide and its receptor PAC(1) were investigated by using in situ hybridization and immunohistochemistry techniques. Our results demonstrated that PACAP and its receptor PAC(1) were highly represented in the testis of these two species. In particular, we showed that they are present within some germ cells and that PACAP, unlike in mammals, is expressed also in the somatic cells (Sertoli and Leydig cells) of the testis of these two non-mammalian vertebrates, suggesting that this neuropeptide is involved in the hormonal control of spermatogenesis and steroidogenesis.
Anna Capaldo - One of the best experts on this subject based on the ideXlab platform.
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histological changes apoptosis and metallothionein levels in Triturus Carnifex amphibia urodela exposed to environmental cadmium concentrations
Aquatic Toxicology, 2016Co-Authors: Anna Capaldo, Ivana Caputo, Carla Esposito, Marilena Lepretti, Rosaria Scudiero, Francesca Trinchella, Anna Marabotti, Vincenza LaforgiaAbstract:Abstract The aim of this study was to verify if the freshwater safety values established from the European Community (1998) and the Italian Ministry of Health (2001) for cadmium (44.5 nM/L in drinking water and 178 nM/L in sewage waters) were safe for amphibians, since at these same concentrations cadmium induced endocrine disruption in the newt Triturus Carnifex . Adult male specimens of T. Carnifex were exposed daily to cadmium (44.5 nM/L and 178 nM/L as CdCl 2 , nominal concentrations), respectively, during 3- and 9-months; at the same time, control newts were exposed to tap water only. The accumulation of cadmium in the skin, liver and kidney, the levels of metallothioneins in the skin and the liver, the expression of metallothionein mRNA in the liver, as well as the presence of histological alterations and of apoptosis in the target organs were evaluated. The 9-months exposure induced cadmium accumulation in all the tissues examined; moreover, histological changes were observed in all the tissues examined, irrespective of the dose or the time of exposure. Apoptosis was only detected in the kidney, whereas metallothioneins and metallothionein mRNA did not increase. This study demonstrates that the existing chronic water quality criterion established for cadmium induces in the newt T. Carnifex cadmium accumulation and histological alterations in the target organs examined. Together with our previous results, showing that, at these same concentrations, cadmium induced endocrine disruption, the present results suggest that the existing chronic water quality criterion for cadmium appears to be not protective of amphibians.
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chronic exposure to cadmium disrupts the adrenal gland activity of the newt Triturus Carnifex amphibia urodela
BioMed Research International, 2013Co-Authors: Vincenza Laforgia, Ivana Caputo, Carla Esposito, Marilena Lepretti, Anna CapaldoAbstract:We intended to verify the safety of the freshwater values established for cadmium by the European Community and the Italian Ministry of Health in drinking water (5 μg/L) and sewage waters (20 μg/L). Therefore, we chronically exposed the newt Triturus Carnifex to 5 μg/L and 20 μg/L doses of cadmium, respectively, during 3 and 9 months and verified the effects on the adrenal gland. We evaluated the serum concentrations of adrenocorticotropic hormone (ACTH), corticosterone, aldosterone, norepinephrine, and epinephrine. During the 3-month exposure, both doses of cadmium decreased ACTH and corticosterone serum levels and increased aldosterone and epinephrine serum levels. During the 9-month exposure, the 5 μg/L dose decreased ACTH and increased aldosterone and epinephrine serum levels; the 20 μg/L dose decreased norepinephrine and epinephrine serum levels, without affecting the other hormones. It was concluded that (1) chronic exposure to the safety values established for cadmium disrupted the adrenal gland activity and (2) the effects of cadmium were related both to the length of exposure and the dose administered. Moreover, our results suggest probable risks to human health, due to the use of water contaminated by cadmium.
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endocrine disrupting effects of nonylphenol in the newt Triturus Carnifex amphibia urodela
Comparative Biochemistry and Physiology C-toxicology & Pharmacology, 2012Co-Authors: Anna Capaldo, Salvatore Valiante, Maria De Falco, Rosaria Sciarrillo, Massimo Maddaloni, Vincenza LaforgiaAbstract:The aim of our study was to verify whether environmental concentrations of nonylphenol influenced the adrenal gland of Triturus Carnifex. Newts were exposed to 19 μg/L nominal concentration of nonylphenol throughout the periods of December-January and March-April, corresponding to different stages of the chromaffin cell functional cycle. The morphological features of the steroidogenic and chromaffin tissues, and the serum levels of ACTH, aldosterone, corticosterone, norepinephrine and epinephrine were evaluated. Nonylphenol did not influence ACTH serum levels. During the two periods examined, the steroidogenic tissue had the same reaction: the quantity of cytoplasmic lipids, and the corticosteroid serum levels, decreased, suggesting the inhibition of synthesis and release of corticosteroids. During the two periods examined, the chromaffin tissue reacted differently to nonylphenol. During December-January, the numeric ratio of norepinephrine granules to epinephrine granules, and the epinephrine serum levels, increased, suggesting the stimulation of epinephrine release. During March-April, the numeric ratio of norepinephrine granules to epinephrine granules did not change, and the norepinephrine serum levels decreased, suggesting the inhibition of norepinephrine release. Our results show that nonylphenol influences the activity of the newt adrenal gland; considering the physiological role of this gland, our results suggest that nonylphenol may contribute to amphibian decline.
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annual and daily serum aldosterone and catecholamine patterns in males of the italian crested newt Triturus Carnifex amphibia urodela
Italian Journal of Zoology, 2010Co-Authors: Salvatore Valiante, Vincenza Laforgia, Rosaria Sciarrillo, M De Falco, Anna CapaldoAbstract:Abstract The present work studied the annual and daily aldosterone, norepinephrine and epinephrine patterns in the newt Triturus Carnifex. The annual variations of the serum aldosterone were evaluated every month by radioimmunoassay, from September to July; the daily variations of this hormone were evaluated in the months of January, April, July and November. Aldosterone levels were low from September to November (lowest value 187.23 ± 19.7 pg/ml in November), increased in December, remained high until March and peaked in April (587.25 ± 58.2 pg/ml). In May, the levels decreased and remained steady until July. Considering the daily aldosterone pattern, in all the examined months, serum aldosterone levels were lowest at 5:00 am (lowest value 162.51 ± 17.4 pg/ml in November) and peaked at 5:00 pm (maximal value 2075.00 ± 213.00 pg/ml in April). As regards the annual catecholamine pattern as measured by HPLC, serum norepinephrine levels were low from September to November (lowest value 541.13 ± 39.8 pg/ml in...
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chromaffin cells in the amphibian urodele Triturus Carnifex show ultrastructural features indicative of a vesicle mediated mode of cell degranulation
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, 2009Co-Authors: Enrico Crivellato, Anna Capaldo, Vincenza Laforgia, Maria De Falco, Domenico Ribatti, Antonio De LucaAbstract:Recently, suggestive evidence for piecemeal degranulation (PMD), a particulate pattern of cell secretion accomplished by vesicle-mediated extracellular transport of granule-stored material, has been provided by electron microscopy investigations in chromaffin cells of different vertebrate species. In this study, chromaffin tissue from the interrenal gland of the amphibian urodede Triturus Carnifex has been investigated by quantitative transmission electron microscopy in search for ultrastructural clues indicative of a vesicle-mediated mode of cell degranulation. Interestingly, a single type of chromaffin cell is recognizable in T. Carnifex, which undergoes seasonal variations in its adrenaline and noradrenaline granule ratio according to an annual cycle that matches the trend of changes in secondary sexual characters. In this study, we looked for a series of ultrastructural changes regarded as highly specific for PMD. We calculated the percentage of (i) resting, unaltered granules (type 1 granules); (ii) granules with changes indicative of progressive release of secretory materials, that is, granules with lucent areas in their cores, reduced electron density, disassembled matrices, and residual cores (type 2 granules); and (iii) membrane empty containers (type 3 granules) in chromaffin cells of T. Carnifex during the annual cycle. We found a significant increase in type 2 and 3 granules, accompanied by a significant decrease in type 1 granules, in the April and November samples. During the same seasonal periods, the number per net cytoplasmic area of 30–100-nm diameter electron-dense vesicles was found to be significantly augmented, and there was also an augmented percentage of chromaffin granules showing blebs or protrusions in their profiles. These ultrastructural data are indicative of an increased vesicle-mediated transport of chromaffin granule products for extracellular release in the amphibian T. Carnifex in accordance with the increased rate of catecholamine release. This vesicle-mediated pattern of cell secretion suits the schema of PMD. In an evolutionary perspective, these findings suggest that PMD is a secretory pathway that has been highly conserved throughout vertebrate classes. Anat Rec, 2009. © 2008 Wiley-Liss, Inc.
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endocrine disrupting effects of nonylphenol in the newt Triturus Carnifex amphibia urodela
Comparative Biochemistry and Physiology C-toxicology & Pharmacology, 2012Co-Authors: Anna Capaldo, Salvatore Valiante, Maria De Falco, Rosaria Sciarrillo, Massimo Maddaloni, Vincenza LaforgiaAbstract:The aim of our study was to verify whether environmental concentrations of nonylphenol influenced the adrenal gland of Triturus Carnifex. Newts were exposed to 19 μg/L nominal concentration of nonylphenol throughout the periods of December-January and March-April, corresponding to different stages of the chromaffin cell functional cycle. The morphological features of the steroidogenic and chromaffin tissues, and the serum levels of ACTH, aldosterone, corticosterone, norepinephrine and epinephrine were evaluated. Nonylphenol did not influence ACTH serum levels. During the two periods examined, the steroidogenic tissue had the same reaction: the quantity of cytoplasmic lipids, and the corticosteroid serum levels, decreased, suggesting the inhibition of synthesis and release of corticosteroids. During the two periods examined, the chromaffin tissue reacted differently to nonylphenol. During December-January, the numeric ratio of norepinephrine granules to epinephrine granules, and the epinephrine serum levels, increased, suggesting the stimulation of epinephrine release. During March-April, the numeric ratio of norepinephrine granules to epinephrine granules did not change, and the norepinephrine serum levels decreased, suggesting the inhibition of norepinephrine release. Our results show that nonylphenol influences the activity of the newt adrenal gland; considering the physiological role of this gland, our results suggest that nonylphenol may contribute to amphibian decline.
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annual and daily serum aldosterone and catecholamine patterns in males of the italian crested newt Triturus Carnifex amphibia urodela
Italian Journal of Zoology, 2010Co-Authors: Salvatore Valiante, Vincenza Laforgia, Rosaria Sciarrillo, M De Falco, Anna CapaldoAbstract:Abstract The present work studied the annual and daily aldosterone, norepinephrine and epinephrine patterns in the newt Triturus Carnifex. The annual variations of the serum aldosterone were evaluated every month by radioimmunoassay, from September to July; the daily variations of this hormone were evaluated in the months of January, April, July and November. Aldosterone levels were low from September to November (lowest value 187.23 ± 19.7 pg/ml in November), increased in December, remained high until March and peaked in April (587.25 ± 58.2 pg/ml). In May, the levels decreased and remained steady until July. Considering the daily aldosterone pattern, in all the examined months, serum aldosterone levels were lowest at 5:00 am (lowest value 162.51 ± 17.4 pg/ml in November) and peaked at 5:00 pm (maximal value 2075.00 ± 213.00 pg/ml in April). As regards the annual catecholamine pattern as measured by HPLC, serum norepinephrine levels were low from September to November (lowest value 541.13 ± 39.8 pg/ml in...
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pituitary adenylate cyclase activating polypeptide and its receptor pac1 in the testis of Triturus Carnifex and podarcis sicula
General and Comparative Endocrinology, 2010Co-Authors: Marisa Agnese, Salvatore Valiante, Vincenza Laforgia, Francesco Angelini, Piero Andreuccetti, Marina PriscoAbstract:The pituitary adenylate cyclase-activating polypeptide (PACAP) is a member of the glucagon-related family that occurs in two amidated forms with 38 (PACAP38) and 27 (PACAP27) amino acids. First discovered in the brain, it was then localized in several peripheral tissues of mammals, including the testis. However, current knowledge of the expression and function of PACAP and its receptor PAC(1) in the reproductive system of non-mammalian vertebrates, and particularly in the testis, is still limited. The aim of this work was to study the presence of PACAP and its receptor PAC(1) in the testis of two non-mammalian vertebrates during the breeding season: the crested newt Triturus Carnifex and the wall lizard Podarcis sicula. The expression and distribution of this neuropeptide and its receptor PAC(1) were investigated by using in situ hybridization and immunohistochemistry techniques. Our results demonstrated that PACAP and its receptor PAC(1) were highly represented in the testis of these two species. In particular, we showed that they are present within some germ cells and that PACAP, unlike in mammals, is expressed also in the somatic cells (Sertoli and Leydig cells) of the testis of these two non-mammalian vertebrates, suggesting that this neuropeptide is involved in the hormonal control of spermatogenesis and steroidogenesis.
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The newt Triturus Carnifex as a model for monitoring the ecotoxic impact of the fungicide thiophanate methyl: adverse effects on the adrenal gland.
Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology, 2006Co-Authors: Anna Capaldo, Salvatore Valiante, Vincenza Laforgia, Maria De Falco, Francesca Virgilio, Lorenzo VaranoAbstract:Abstract The aims of this study were to propose a bioindicator organism, the newt Triturus Carnifex , for the assessment of toxicological impact of thiophanate methyl in the Campania region (Italy) and the possible adverse activity on the adrenal gland. In the acute toxicity study, experimental groups of T. Carnifex were exposed to 2.40, 4.80, 9.60 and 19.20 μg/L tap water of thiophanate methyl for 2 days; the LD 50 was found to be 9.60 μg/L. To evaluate the effects on the adrenal gland, newts were exposed to a dose of 25% of the LD 50 2 days for 8 days. The ultrastructural features of the tissues as well as the serum levels of aldosterone, corticosterone, norepinephrine (NE) and epinephrine (E) were evaluated. The number of secretory vesicles in the chromaffin cells appeared significantly decreased, whereas NE and E serum levels appeared strongly increased. Moreover, corticosterone and aldosterone serum levels appeared significantly reduced. The results suggest that: 1) T. Carnifex has the features of an ideal bioindicator, due to its high sensitivity to thiophanate methyl, 2) thiophanate methyl acts as endocrine disruptor, affecting the adrenal gland at very low doses, 3) thiophanate methyl may be toxic for nontarget organisms, such as newts.
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release of aldosterone and catecholamines from the interrenal gland of Triturus Carnifex in response to adrenocorticotropic hormone acth administration
Journal of Morphology, 2004Co-Authors: Anna Capaldo, Salvatore Valiante, M G Varlese, Vincenza Laforgia, Lorenzo VaranoAbstract:The influence of adrenocorticotropic hor- mone (ACTH) on the interrenal gland of Triturus Carnifex was investigated by in vivo administration of synthetic ACTH. The effects were evaluated by examination of the ultrastructural morphological and morphometrical fea- tures of the tissues as well as the circulating serum levels of aldosterone, noradrenaline (NA), and adrenaline (A). In June and November, ACTH administration increased al- dosterone release (from 281.50 1.60 pg/ml in carrier- injected newts to 597.02 3.35 pg/ml in June; from 187.45 1.34 pg/ml in carrier-injected animals to 651.00 3.61 pg/ml in November). The steroidogenic cells showed clear signs of stimulation, together with a reduc- tion of lipid content in June and an increase of lipid content in November. Moreover, ACTH administration decreased the mean total number of secretory vesicles in the chromaffin cells in June (from 7.73 0.60 granules/ m 2 in carrier-injected animals to 5.91 0.40 granules/ m 2 ) and November (from 7.78 0.75 granules/m 2 in carrier-injected newts to 4.87 0.40 granules/m 2 ). In June, however, when T. Carnifex chromaffin cells contain almost exclusively NA granules (NA: 7.42 0.86 gran- ules/m 2 ; A: 0.32 0.13 granules/m 2 ), ACTH decreased NA content (5.52 0.32 granules/m 2 ) increasing NA release (from 639.82 3.30 pg/ml in carrier-injected to 880.55 4.52 pg/ml). In November, when both cat- echolamines, NA (3.92 0.34 granules/m 2 ) and A (3.84 0.33 granules/m 2 ), are present in the chromaffin cells, ACTH administration reduced A content (1.02 0.20 granules/m 2 ), enhancing adrenaline secretion (from 681.30 3.62 pg/ml in carrier-injected newts to 1,335.73 9.03 pg/ml). The results of this study indicate that ACTH influences the steroidogenic tissue, eliciting aldosterone release. The effects on the chromaffin tissue, increase of NA or A secretion, according to the period of chromaffin cell functional cycle, may be direct and/or me- diated through the increase of aldosterone release. Fi- nally, the lack of an increase of A content in the chromaf- fin cells, or A serum level, following ACTH administration in June might suggest an independence of PNMT enzyme on corticosteroids. J. Morphol. 262:692-700, 2004. © 2004 Wiley-Liss, Inc.
