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Ewa Kulczykowska - One of the best experts on this subject based on the ideXlab platform.
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nonapeptides Arginine Vasotocin and isotocin in fishes advantage of bioactive molecules measurement
Frontiers in Marine Science, 2020Co-Authors: Ewa Sokolowska, Magdalena Gozdowska, Ewa KulczykowskaAbstract:The aim of this article is to share with fish physiologists and behaviourists our thoughts and hints regarding the involvement of nonapeptides in various physiological and behavioural processes in fishes and the advantage of measurements of bioavailable molecules. Arginine Vasotocin (AVT) and isotocin (IT) are biologically active nonapeptides in teleosts which are produced in separate neurosecretory neurons in the hypothalamic nuclei. They act as neurotransmitters and/or neuromodulators in the central nervous system (CNS) or as peripheral hormones, when they are released in the neurohypophysis and distributed via the bloodstream. Biosynthesis of bioactive AVT and IT is a complicated multistage process and nonapeptides have multiple sites of action. Different analytical approaches, including determination of pro-AVT and pro-IT mRNA in the hypothalamus or AVT and IT concentration in the brain, pituitary and plasma are used depending on the aim of the study. However, the level of biologically-active molecules is more straightforwardly related to their current action in the CNS and/or peripheral organs compared with indirect proxies of nonapeptides production such as the expression of pro-peptides mRNA. Therefore analysis of AVT and IT is highly recommended in many studies. Herein we compiled various works in which bioavailable AVT and IT were analysed in order to highlight the importance of such approach. Moreover, we compared the fluctuation of nonapeptide levels in the plasma with that in the brain of round gobies in successive reproductive phases. We also showed that neither AVT nor IT level was associated with fish age.
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annual changes in brain concentration of Arginine Vasotocin and isotocin correspond with phases of reproductive cycle in round goby neogobius melanostomus
Chronobiology International, 2015Co-Authors: Ewa Sokolowska, Agnieszka Kleszczynska, M Nietrzeba, Ewa KulczykowskaAbstract:Reproductive cycle of seasonally breeding fish is synchronized with changes of photoperiod and temperature in environment. We hypothesize that Arginine Vasotocin (AVT) and isotocin (IT) are involved in timing and synchronization of seasonal reproductive activity in the round goby (Neogobius melanostomus). To verify this hypothesis, we examined the annual profiles of brain AVT and IT in round goby males and females in relation to their reproductive cycle. Wild round gobies were exposed to annual environmental changes in their natural habitats from where they were sampled monthly over a year. AVT and IT were measured using HPLC with fluorescence detection preceded by solid-phase extraction. This study shows seasonal variations in brain AVT and IT levels. Profiles of changes were similar in males and females: the peak of AVT was observed before spawning in March-April, whereas that of IT during spawning in May–June. Furthermore, the lowest AVT level was noted out of breeding season from November to January, ...
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neuropeptides isotocin and Arginine Vasotocin in urophysis of three fish species
Fish Physiology and Biochemistry, 2013Co-Authors: Magdalena Gozdowska, Marek ślebioda, Ewa KulczykowskaAbstract:In this study, for the first time, both neuropeptides isotocin (IT) and Arginine Vasotocin (AVT) have been identified and measured in urophysis, the neurohaemal organ of the caudal neurosecretory system of teleost fish. So far, AVT, but not IT, was quantified by radioimmunoassay (RIA) in urophysis of several fish species. We have used high-performance liquid chromatographic assay with fluorescence detection (HPLC-FL) preceded by solid-phase extraction (SPE) and liquid chromatography-electrospray ionization triple-quadrupole tandem mass spectrometry (LC-ESI MS/MS) technique to determine both neuropeptides in urophysis of three fish species. The efficiency of peptide’s SPE extraction was 79–85 %. In HPLC-FL method, the limits of detection (LOD) and quantification (LOQ) were estimated as 1.0 and 3.4 pmol/mL for IT and 0.25 and 2.20 pmol/mL for AVT. In LC–MS/MS method, LOD and LOQ were estimated as 0.4 and 1.2 pmol/mL for IT and 0.06 and 0.2 pmol/mL for AVT. The chromatographic methods are good alternative for RIA, because enable to measure both nonapeptides simultaneously in one sample. In round goby (Neogobius melanostomus), three-spined stickleback (Gasterosteus aculeatus) and sea bream (Sparus aurata), urophysial IT concentrations ranged between 0.056 and 0.678 pmol/mg tissue and AVT concentrations ranged between 0.0008 (or even below detection threshold) and 0.084 pmol/mg tissue.
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stocking density influences brain Arginine Vasotocin avt and isotocin it levels in males and females of three spined stickleback gasterosteus aculeatus
General and Comparative Endocrinology, 2013Co-Authors: Agnieszka Kleszczynska, Ewa KulczykowskaAbstract:Arginine Vasotocin (AVT) and isotocin (IT) are fish neurohormones produced in separate parvocellular and magnocellular preoptic neurons of Teleostei. Apart from well-established peripheral action as hormones they are important neurotransmitters in central nervous system in fish. In the present study, we examined an influence of stocking density on whole brain AVT and IT concentrations in males and females of three-spined stickleback (Gasterosteus aculeatus). In males, the highest AVT levels have been found at stocking densities of 10 and 30 individuals per 30-l tank. On the other hand, in females, AVT concentration was significantly higher in those kept alone. Brain IT concentrations significantly increased along with stocking density only in females and did not change in males. The sex-dependent responses indicate a different stimulation of AVT and IT neurons in males and females. Consequently, roles of the neurohormones in males and females exposed to stress of overcrowding must be different.
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variation in brain Arginine Vasotocin avt and isotocin it levels with reproductive stage and social status in males of three spined stickleback gasterosteus aculeatus
General and Comparative Endocrinology, 2012Co-Authors: Agnieszka Kleszczynska, Ewa Sokolowska, Ewa KulczykowskaAbstract:Abstract Arginine Vasotocin (AVT) and isotocin (IT) are fish nonapeptides synthesized in separate hypothalamic neurons from where they are transported to the neurohypophysis for storage and release into circulation. AVT is known to modulate aggression, courtship and parental care or social communication in many species, including fish, amphibians and birds. In this paper we examined a link between the level of AVT and IT in the brain and particular reproductive behavior in males of three-spined stickleback ( Gasterosteus aculeatus ). AVT and IT levels in whole brain of males of three-spined stickleback vary depending on specific breeding behavior of the individuals and their social status. These studies have shown the highest AVT levels in aggressive males that took care of the eggs. Brain AVT concentrations are also increased in nuptial colored subordinate males that fight to change their social status. On the other hand, IT is significantly higher in aggressive dominant males that defend their territory. IT may be also involved in courtship in three-spined stickleback. These findings highlight the importance of determination of “free”, bioavailable neuropeptides’ level in behavioral studies.
Agnieszka Kleszczynska - One of the best experts on this subject based on the ideXlab platform.
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annual changes in brain concentration of Arginine Vasotocin and isotocin correspond with phases of reproductive cycle in round goby neogobius melanostomus
Chronobiology International, 2015Co-Authors: Ewa Sokolowska, Agnieszka Kleszczynska, M Nietrzeba, Ewa KulczykowskaAbstract:Reproductive cycle of seasonally breeding fish is synchronized with changes of photoperiod and temperature in environment. We hypothesize that Arginine Vasotocin (AVT) and isotocin (IT) are involved in timing and synchronization of seasonal reproductive activity in the round goby (Neogobius melanostomus). To verify this hypothesis, we examined the annual profiles of brain AVT and IT in round goby males and females in relation to their reproductive cycle. Wild round gobies were exposed to annual environmental changes in their natural habitats from where they were sampled monthly over a year. AVT and IT were measured using HPLC with fluorescence detection preceded by solid-phase extraction. This study shows seasonal variations in brain AVT and IT levels. Profiles of changes were similar in males and females: the peak of AVT was observed before spawning in March-April, whereas that of IT during spawning in May–June. Furthermore, the lowest AVT level was noted out of breeding season from November to January, ...
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urotensin ii inhibits Arginine Vasotocin and stimulates isotocin release from nerve endings in the pituitary of gilthead sea bream sparus aurata
Journal of Experimental Zoology, 2014Co-Authors: Hanna Kalamarzkubiak, Agnieszka Kleszczynska, Iris Meiri Ashkenazi, Hanna RosenfeldAbstract:The aim of this in vitro study was to determine whether Arginine Vasotocin (AVT) and isotocin (IT) release from nerve endings is affected by urotensin II (UII) in gilthead sea bream pituitary. Primary cultures of pituitary cells were exposed to 10−12, 10−10, and 10−8 M UII for 6, 24, and 48 hr. AVT and IT contents were determined in the culture media by high performance liquid chromatography (HPLC). UII at all doses decreased AVT release after 6, 24, and 48 hr of incubation. IT release was increased by UII only after 24 hr of incubation. This study, for the first time, indicates that UII affects AVT and IT release from nerve endings in the pituitary of Sparus aurata. It is presumed that UII together with AVT and IT may control response to different salinities in fishes. J. Exp. Zool. 321A: 467–471, 2014. © 2014 Wiley Periodicals, Inc.
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in vitro effect of cortisol and urotensin i on Arginine Vasotocin and isotocin secretion from pituitary cells of gilthead sea bream sparus aurata
Journal of Fish Biology, 2014Co-Authors: Hanna Kalamarzkubiak, Agnieszka Kleszczynska, I Meiriashkenazi, Hanna RosenfeldAbstract:This study aimed at determining whether in vitro secretion of two neuropeptides, Arginine Vasotocin (AVT) and isotocin (IT), from pituitary cells of gilthead sea bream Sparus aurata was affected by cortisol and urotensin (UI). Pituitary cells were exposed to 1·4 × 10(-8) , 1·4 × 10(-7) and 0·4 × 10(-6) M cortisol and 10(-12) , 10(-10) and 10(-8) M UI for 6, 24 and 48 h, respectively. AVT and IT contents were determined in the culture media by high-performance liquid chromatography (HPLC). An increase in AVT secretion and a decrease in IT secretion were observed at all cortisol doses. UI increased AVT secretion after 6 h of incubation at all doses. After 24 h, however, only the highest dose of UI still displayed an effect. IT secretion was not influenced by UI. It was thus demonstrated that cortisol does influence AVT and IT secretion from S. aurata pituitary cells, while UI regulates AVT secretion, as a component of hypothalamic-pituitary-interrenal (HPI) axis in this species.
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stocking density influences brain Arginine Vasotocin avt and isotocin it levels in males and females of three spined stickleback gasterosteus aculeatus
General and Comparative Endocrinology, 2013Co-Authors: Agnieszka Kleszczynska, Ewa KulczykowskaAbstract:Arginine Vasotocin (AVT) and isotocin (IT) are fish neurohormones produced in separate parvocellular and magnocellular preoptic neurons of Teleostei. Apart from well-established peripheral action as hormones they are important neurotransmitters in central nervous system in fish. In the present study, we examined an influence of stocking density on whole brain AVT and IT concentrations in males and females of three-spined stickleback (Gasterosteus aculeatus). In males, the highest AVT levels have been found at stocking densities of 10 and 30 individuals per 30-l tank. On the other hand, in females, AVT concentration was significantly higher in those kept alone. Brain IT concentrations significantly increased along with stocking density only in females and did not change in males. The sex-dependent responses indicate a different stimulation of AVT and IT neurons in males and females. Consequently, roles of the neurohormones in males and females exposed to stress of overcrowding must be different.
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variation in brain Arginine Vasotocin avt and isotocin it levels with reproductive stage and social status in males of three spined stickleback gasterosteus aculeatus
General and Comparative Endocrinology, 2012Co-Authors: Agnieszka Kleszczynska, Ewa Sokolowska, Ewa KulczykowskaAbstract:Abstract Arginine Vasotocin (AVT) and isotocin (IT) are fish nonapeptides synthesized in separate hypothalamic neurons from where they are transported to the neurohypophysis for storage and release into circulation. AVT is known to modulate aggression, courtship and parental care or social communication in many species, including fish, amphibians and birds. In this paper we examined a link between the level of AVT and IT in the brain and particular reproductive behavior in males of three-spined stickleback ( Gasterosteus aculeatus ). AVT and IT levels in whole brain of males of three-spined stickleback vary depending on specific breeding behavior of the individuals and their social status. These studies have shown the highest AVT levels in aggressive males that took care of the eggs. Brain AVT concentrations are also increased in nuptial colored subordinate males that fight to change their social status. On the other hand, IT is significantly higher in aggressive dominant males that defend their territory. IT may be also involved in courtship in three-spined stickleback. These findings highlight the importance of determination of “free”, bioavailable neuropeptides’ level in behavioral studies.
Katuhide Tanaka - One of the best experts on this subject based on the ideXlab platform.
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appearance of an Arginine Vasotocin receptor of large molecular size in the uterus shell gland of the hen at oviposition
Reproduction, 1997Co-Authors: Toru Takahashi, M Kawashima, T Yasuoka, Katuhide TanakaAbstract:The molecular mass of the Arginine Vasotocin receptor in membrane fractions of the uterus (shell gland) of hens was estimated by autoradiography of [ 125 I]-labelled Arginine Vasotocin binding protein after SDS-PAGE. A band of approximately 67 kDa was found in all of the samples taken from laying hens before and after oviposition and from nonlaying hens. In addition to this band, another band of approximately 95 kDa was found in samples from laying hens taken immediately before and after oviposition. Both bands were reduced by the presence of unlabelled Arginine Vasotocin or mesotocin, but the reduction was greater by Arginine Vasotocin than by mesotocin. These two bands were not reduced by chicken luteinizing hormone-releasing hormone-I (Gln 8 -GnRH), chicken luteinizing hormone-releasing hormone-II (His 5 ,Trp 7 ,Tyr 8 -GnRH) and chicken angiotensin-β (Val 5 -angiotensin-II). The appearance of the Arginine Vasotocin receptor of the larger molecular size may be related to oviposition in hens.
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diuretic and antidiuretic effects of mesotocin as compared with the antidiuretic effect of Arginine Vasotocin in the hen
Poultry Science, 1995Co-Authors: Tetsuya Takahashi, Mitsuo Kawashima, Tadashi Yasuoka, Michiharu Kamiyoshi, Katuhide TanakaAbstract:Abstract Mesotocin and Arginine Vasotocin were injected intravenously once at various dosage levels (.0025 to 25 μg/kg body weight) immediately after an intravenous injection of 15 mL/kg body weight saline solution into hens in which an artificial anus had been surgically created, and the volume of urine excreted during a 5-h period, following the injection, was measured. Arginine Vasotocin caused a monophasic, dose-dependent decrease in urine volume. By contrast, mesotocin was biphasic: at .025 and .25 μg/kg body weight it decreased urine volume with the same efficacy as Arginine Vasotocin, whereas it dramatically increased urine volume at the higher doses (2.5 and 25 μg/kg body weight).
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Arginine Vasotocin receptor binding in the hen uterus shell gland before and after oviposition
European Journal of Endocrinology, 1994Co-Authors: Tetsuya Takahashi, Mitsuo Kawashima, Michiharu Kamiyoshi, Katuhide TanakaAbstract:The binding affinity and capacity of Arginine Vasotocin (AVT) receptor in the hen uterus changed during a period before and after oviposition. Three hours before oviposition, the binding capacity of the AVT receptor increased. An injection of prostaglandin (PG) F2 alpha caused an increase in the AVT receptor Bmax in the uterus, and indomethacin blocked the normal rise in the AVT receptor Bmax and PGF content prior to oviposition. However, just prior to oviposition, the binding affinity increased with a decrease in the binding capacity. A progesterone injection caused an increase in binding affinity and a decrease in binding capacity of the AVT receptor. The specific binding of the progesterone receptor in the uterus increased 2 h before oviposition and remained high until oviposition. Serum AVT levels increased at oviposition. An injection of AVT caused an increase in the affinity of the AVT receptor with a decrease in the capacity. The change in the affinity and capacity of AVT receptor at oviposition may result from the action of progesterone via increased progesterone receptor binding, and the action of AVT on its own receptors.
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Arginine Vasotocin binding component in the uterus shell gland of the chicken
European Journal of Endocrinology, 1992Co-Authors: Tetsuya Takahashi, Mitsuo Kawashima, Michiharu Kamiyoshi, Katuhide TanakaAbstract:The plasma membrane fraction of the uterus of the chicken was found to contain a component that shows specific binding to Arginine Vasotocin (AVT), Arginine vasopressin (AVP) and oxytocin (OT). This binding component possesses a higher affinity to AVT than to AVP or OT, and the affinity to AVT was higher in laying hens than in non-laying hens and immature pullets, while the maximum number of binding sites per mg protein was less in the laying hens. Intramuscular injections of either estradiol-17 beta, progesterone or testosterone into the immature pullets for six consecutive days caused an increase in the affinity and number of binding sites. The results suggest that AVT receptors are present in the chicken uterus and that their binding properties are affected by ovarian steroid hormones.
Lawrence E Cornett - One of the best experts on this subject based on the ideXlab platform.
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impact of estrogen and photoperiod on Arginine Vasotocin and vt3 receptor expression in the shell gland of quail
Frontiers in Bioscience, 2018Co-Authors: Rashmi Srivastava, Lawrence E Cornett, Chandra Mohini ChaturvediAbstract:Role of estrogen and photoperiod is well-established in avian reproduction. In addition, the distribution and the expression of Arginine Vasotocin (AVT) and its receptor VT3 to ensure reproductive/breeding conditions in Japanese quail influenced by them has been the main focus of this review. To consider this aspect the mRNA expression of VT3 receptor and its ligand AVT in the shell gland has been emphasized. In birds, AVT performs a dual role as an anti-diuretic hormone and the functions accomplished by oxytocin in mammals. The physiological actions of AVT in birds are mediated through its diverse receptor subtypes VT1, VT2, VT3 and VT4. Dynamic alteration of VT3 expression during different reproductive and photo-sexual conditions of quail can be modulated by estrogen. In addition to the endocrine effect of AVT, the shell gland is complemented by its paracrine action via its receptors. Evidences indicate that the expression of shell gland AVT modulated by estrogen appears to play a priming role by modulating the availability of VT3 receptor for the required action of neurohypophysial AVT during oviposition.
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water deprivation and circadian changes in plasma Arginine Vasotocin and mesotocin in the domestic hen gallus domesticus
Chronobiology International, 2001Co-Authors: Chandra Mohini Chaturvedi, Adity Chowdhury, Lawrence E CornettAbstract:Possible circadian variations in plasma levels of Arginine Vasotocin (AVT) and mesotocin (MT) were assessed in domestic hens (Gallus domesticus) under a 12h:12h light-dark (LD) schedule. Blood samples were taken at 4h intervals, and neurohypophyseal hormone levels were determined by radioimmunoassay. Marked circadian changes in both AVT and MT were observed in hens provided free access to water. Minimal and maximal AVT levels occurred at 08:00 and 20:00, respectively. Minimal MT levels occurred at 20:00, whereas maximal MT levels occurred over a broad time period of 04:00 to 12:00. In water-deprived hens, plasma AVT levels were elevated at each time point, and the circadian variations in plasma AVT and MT levels were attenuated. These results demonstrate that rhythmicity in neurohypophyseal function in a lower vertebrate species, like that in mammals, is disrupted by osmotic stress.
Sakae Kikuyama - One of the best experts on this subject based on the ideXlab platform.
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Localization of three types of Arginine Vasotocin receptors in the brain and pituitary of the newt Cynops pyrrhogaster
Cell and Tissue Research, 2010Co-Authors: Itaru Hasunuma, Fumiyo Toyoda, Yoshihiko Kadono, Hideo Namiki, Sakae KikuyamaAbstract:The distribution of three types of Arginine Vasotocin (AVT) receptors in the brain and pituitary of the newt Cynops pyrrhogaster , namely, the V1a-, V2-, and V3/V1b-type receptors, was studied by means of in situ hybridization and immunohistochemistry. mRNA signals and immunoreactive cells for the V1a-type receptor were observed in the telencephalon (mitral layer of the olfactory bulb, dorsal and medial pallium, lateral and medial amygdala, bed nucleus of the decussation of the fasciculus telencephali, bed nucleus of the stria terminalis), diencephalon (anterior preoptic area, magnocellular preoptic nucleus, suprachiasmatic nucleus, ventral thalamus, dorsal and ventral hypothalamic nucleus), mesencephalon (tegmentum, interpeduncular nucleus), and medulla oblongata (median reticular formation, nucleus motorius tegmenti). Cells expressing the V2-type receptor were found in the telencephalon (medial pallium, lateral and medial amygdala, bed nucleus of the decussation of the fasciculus telencephali), and mesencephalon (tegmentum trigemini and facialis). In the paraphysis (possibly the main site of cerebrospinal fluid production), only V2-type receptor mRNA signal and immunoreactivity were detected. V3/V1b-type receptor mRNA was expressed in the diencephalon (dorsal hypothalamic nucleus, nucleus tuberculi posterioris), mesencephalon (tegmentum, interpeduncular nucleus), and medulla oblongata (raphe nucleus), whereas V3/V1b-type-receptor-like immunoreactivity was scarcely detectable in the entire brain. The V3/V1b-type receptor was predominantly expressed in the anterior pituitary. V3/V1b-type receptor and proopiomelanocortin mRNAs were co-localized in the distal lobe of the pituitary. This is the first report of the distribution of three types of AVT receptor in the brain and pituitary of non-mammalian vertebrates.
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molecular cloning of three types of Arginine Vasotocin receptor in the newt cynops pyrrhogaster
General and Comparative Endocrinology, 2007Co-Authors: Itaru Hasunuma, Fumiyo Toyoda, Tomoaki Nakada, Hideo Namiki, Toshihiko Sakai, Sakae KikuyamaAbstract:Three types of cDNA encoding the Arginine Vasotocin (AVT) receptors from the newt, Cynops pyrrhogaster were cloned and the gene expression of each receptor analyzed in the organs and tissues of the newt. The deduced amino acid sequence of one type of AVT receptor, consisting of 418 amino acid residues, showed a high degree of sequence identity with the mammalian Arginine vasopressin (AVP) V1a receptors (61–68%). The second type of cDNA, encoding an amino acid sequence consisting of 367 amino acid residues, exhibited a relatively high sequence identity with mammalian AVP V2 receptors (50–51%). The third cDNA, encoding a sequence of 415 amino acid residues, possessed high sequence identity with mammalian AVP V3/V1b receptors (59–63%). Phylogenetic analysis revealed that the first, second and third types of receptor were close to mammalian AVP V1a, V2 and V3/V1b receptors, respectively, and RT-PCR using gene specific primers for each type of receptor indicated that the first and second types of receptor mRNA were expressed in various organs and tissues, including the circulatory, osmoregulatory, and reproductive organs of both male and female newts. In contrast, mRNA expression of the third cDNA was mainly detected in the brain and pituitary, and its expression pattern was distinctly different from that of the other two. We suggest that the first, second and third types of newt AVT receptor obtained in the present study are counterparts of mammalian AVP V1a, V2 and V3/V1b receptors, respectively.
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involvement of Arginine Vasotocin in reproductive events in the male newt cynops pyrrhogaster
Hormones and Behavior, 2003Co-Authors: Fumiyo Toyoda, Yoichi Ito, Kazutoshi Yamamoto, Shigeyasu Tanaka, Masayuki Yamashita, Sakae KikuyamaAbstract:Abstract Effects of Arginine Vasotocin (AVT) on reproductive events such as courtship behavior, pheromone release, and spermatophore discharge were investigated in the male newt Cynops pyrrhogaster. AVT enhanced the incidence and frequency of androgen-induced courtship behavior. In this case, AVT was likely to act centrally because the behavior was evoked with a much smaller amount of AVT when the hormone was administered intracerebroventricularly than when given intraperitoneally. Involvement of endogenous AVT in spontaneously occurring courtship behavior was also evidenced by the fact that administration of a V1 (vasopressor) receptor antagonist, [d(CH2)51, Tyr(Me)2, Arg8-vasopressin] suppressed the expression of the courtship behavior. The water in which AVT-treated males had been kept showed considerable female-attracting activity as compared with the water in which saline-injected males had been kept. Moreover, the content of sodefrin, a female-attracting pheromone in the abdominal gland, was decreased by the intraperitoneal injection of AVT, suggesting that the neurohypophyseal hormone stimulated the release of sodefrin from the abdominal gland into the water. AVT induced contraction of the excised abdominal gland concentration-dependently, and, again, the V1 receptor antagonist suppressed the AVT-induced contraction. Thus, we concluded that AVT induces the pheromone discharge, acting peripherally on a contractile structure of the abdominal gland. AVT was also found to induce spermatophore deposition in the male kept in the absence of the female. Administration of the V1 receptor blocker to the sexually developed males suppressed the spermatophore deposition. All these results indicate the involvement of AVT in reproductive events acting centrally and peripherally.