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Gastone G. Nussdorfer - One of the best experts on this subject based on the ideXlab platform.
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a morphometric study of the effects of melatonin on the rat adrenal Zona Glomerulosa
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: Piera Rebuffat, G Mazzocchi, A Stachowiak, A S Belloni, Gastone G. NussdorferAbstract:: The effects of a long-term administration of melatonin on the Zona Glomerulosa were investigated both in "normal" rats and in animals in which the hypothalamo-hypophyseal-adrenal axis and the renin-angiotensin system had been pharmacologically interrupted. Melatonin caused a notable hypertrophy of Zona Glomerulosa cells and a significant rise in the plasma concentration of aldosterone in both groups of rats. These findings indicate that melatonin exerts in vivo a strong direct stimulatory action on the growth and steroidogenic capacity of the rat Zona Glomerulosa.
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long term trophic effect of sodium restriction on the rat adrenal Zona Glomerulosa i its partial independence of the renin angiotensin system
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: Claudia Robba, G Mazzocchi, Piera Rebuffat, Gastone G. NussdorferAbstract:: The mechanism of the trophic effect of chronic sodium restriction on the Zona Glomerulosa of the rat adrenals was investigated by combined morphometric and biochemical techniques. In the normal rats, prolonged sodium deprivation caused a significant hypertrophy of the Zona Glomerulosa and its parenchymal cells, coupled with a conspicuous rise in the plasma concentration of aldosterone. Analogous results were observed in animals simultaneously administered captopril and maintenance doses of angiotensin II. However, in this last case, the changes were significantly lower than those observed in the normal rats. These findings are compatible with the view that the activation of the renin-angiotensin system is not the sole mechanism involved in the stimulation of the growth and steroidogenic capacity of rat adrenal Zona Glomerulosa induced by chronic sodium restriction.
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short and long term effects of angiotensin ii on the rat adrenal Zona Glomerulosa a coupled stereological and enzymological study
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: Gastone G. Nussdorfer, Piera Rebuffat, G Mazzocchi, Ludwik K Malendowicz, Aldona Kasprzak, C RobbaAbstract:: Long-term angiotensin II administration induced a time-dependent increase in the volume of rat Zona Glomerulosa cells and in the plasma concentration of aldosterone. Cell hypertrophy is coupled with comparable increases in the surface area per cell of mitochondrial cristae and in the activity per cell of 18-hydroxylase. 11 beta-hydroxylase activity was not affected. These findings allow to suggest that the angiotensin-II-enhanced growth of rat Zona Glomerulosa is associated with the de novo synthesis of 18-hydroxylase.
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long term trophic effect of sodium restriction on the rat adrenal Zona Glomerulosa ii the possible involvement of the inhibition of the dopaminergic system
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: C Robba, G Mazzocchi, Piera Rebuffat, Gastone G. NussdorferAbstract:: The effects of chronic administration of metoclopramide or bromocriptine (two drugs which act as antagonist and agonist of dopamine receptors) on the Zona Glomerulosa of captopril-treated rats administered maintenance doses of angiotensin II, were investigated by combined morphometric and biochemical techniques. It was found that metoclopramide provoked a significant hypertrophy of the Zona Glomerulosa and its parenchymal cells, coupled with a persistent rise in the plasma concentration of aldosterone, only in rats fed a normal diet. Conversely, bromocriptine exerted an evident inhibitory effect on the Zona Glomerulosa growth and steroidogenic capacity only in chronically sodium-deprived animals. These findings strongly suggest that sodium balance modulates the activity of the dopaminergic system, whose chronic suppression may be involved in the mechanism underlying the extra-angiotensin adrenoglomerulotrophic effect of prolonged sodium restriction.
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further studies on the involvement of dopamine and somatostatin in the inhibitory control of the growth and steroidogenic capacity of rat adrenal Zona Glomerulosa
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: Piera Rebuffat, G Mazzocchi, Giuseppe Gottardo, Gastone G. NussdorferAbstract:: Prolonged (12-day) sodium restriction increased basal plasma concentration of aldosterone and provoked a notable hypertrophy of the Zona Glomerulosa and its cells in rats. A 7-day infusion of dopamine or somatostatin, at a rate which was found to exert a maximum inhibition of aldosterone secretion in 12 h, only partially reversed the effects of sodium deprivation. However, the combined administration of these two molecules not only completely annulled the effects of sodium restriction, but also lowered plasma aldosterone concentration and the volumes of the Zona Glomerulosa and its cells below the values found in rats fed a normal diet. These findings confirm the contention that dopamine and somatostatin are both involved in the negative control of the growth and steroidogenic capacity of the rat Zona Glomerulosa, and suggest that different mechanisms underlie the antiadrenoglomerulotrophic action of these molecules.
Piera Rebuffat - One of the best experts on this subject based on the ideXlab platform.
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a morphometric study of the effects of melatonin on the rat adrenal Zona Glomerulosa
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: Piera Rebuffat, G Mazzocchi, A Stachowiak, A S Belloni, Gastone G. NussdorferAbstract:: The effects of a long-term administration of melatonin on the Zona Glomerulosa were investigated both in "normal" rats and in animals in which the hypothalamo-hypophyseal-adrenal axis and the renin-angiotensin system had been pharmacologically interrupted. Melatonin caused a notable hypertrophy of Zona Glomerulosa cells and a significant rise in the plasma concentration of aldosterone in both groups of rats. These findings indicate that melatonin exerts in vivo a strong direct stimulatory action on the growth and steroidogenic capacity of the rat Zona Glomerulosa.
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long term trophic effect of sodium restriction on the rat adrenal Zona Glomerulosa i its partial independence of the renin angiotensin system
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: Claudia Robba, G Mazzocchi, Piera Rebuffat, Gastone G. NussdorferAbstract:: The mechanism of the trophic effect of chronic sodium restriction on the Zona Glomerulosa of the rat adrenals was investigated by combined morphometric and biochemical techniques. In the normal rats, prolonged sodium deprivation caused a significant hypertrophy of the Zona Glomerulosa and its parenchymal cells, coupled with a conspicuous rise in the plasma concentration of aldosterone. Analogous results were observed in animals simultaneously administered captopril and maintenance doses of angiotensin II. However, in this last case, the changes were significantly lower than those observed in the normal rats. These findings are compatible with the view that the activation of the renin-angiotensin system is not the sole mechanism involved in the stimulation of the growth and steroidogenic capacity of rat adrenal Zona Glomerulosa induced by chronic sodium restriction.
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short and long term effects of angiotensin ii on the rat adrenal Zona Glomerulosa a coupled stereological and enzymological study
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: Gastone G. Nussdorfer, Piera Rebuffat, G Mazzocchi, Ludwik K Malendowicz, Aldona Kasprzak, C RobbaAbstract:: Long-term angiotensin II administration induced a time-dependent increase in the volume of rat Zona Glomerulosa cells and in the plasma concentration of aldosterone. Cell hypertrophy is coupled with comparable increases in the surface area per cell of mitochondrial cristae and in the activity per cell of 18-hydroxylase. 11 beta-hydroxylase activity was not affected. These findings allow to suggest that the angiotensin-II-enhanced growth of rat Zona Glomerulosa is associated with the de novo synthesis of 18-hydroxylase.
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long term trophic effect of sodium restriction on the rat adrenal Zona Glomerulosa ii the possible involvement of the inhibition of the dopaminergic system
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: C Robba, G Mazzocchi, Piera Rebuffat, Gastone G. NussdorferAbstract:: The effects of chronic administration of metoclopramide or bromocriptine (two drugs which act as antagonist and agonist of dopamine receptors) on the Zona Glomerulosa of captopril-treated rats administered maintenance doses of angiotensin II, were investigated by combined morphometric and biochemical techniques. It was found that metoclopramide provoked a significant hypertrophy of the Zona Glomerulosa and its parenchymal cells, coupled with a persistent rise in the plasma concentration of aldosterone, only in rats fed a normal diet. Conversely, bromocriptine exerted an evident inhibitory effect on the Zona Glomerulosa growth and steroidogenic capacity only in chronically sodium-deprived animals. These findings strongly suggest that sodium balance modulates the activity of the dopaminergic system, whose chronic suppression may be involved in the mechanism underlying the extra-angiotensin adrenoglomerulotrophic effect of prolonged sodium restriction.
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further studies on the involvement of dopamine and somatostatin in the inhibitory control of the growth and steroidogenic capacity of rat adrenal Zona Glomerulosa
Experimental and Clinical Endocrinology & Diabetes, 2009Co-Authors: Piera Rebuffat, G Mazzocchi, Giuseppe Gottardo, Gastone G. NussdorferAbstract:: Prolonged (12-day) sodium restriction increased basal plasma concentration of aldosterone and provoked a notable hypertrophy of the Zona Glomerulosa and its cells in rats. A 7-day infusion of dopamine or somatostatin, at a rate which was found to exert a maximum inhibition of aldosterone secretion in 12 h, only partially reversed the effects of sodium deprivation. However, the combined administration of these two molecules not only completely annulled the effects of sodium restriction, but also lowered plasma aldosterone concentration and the volumes of the Zona Glomerulosa and its cells below the values found in rats fed a normal diet. These findings confirm the contention that dopamine and somatostatin are both involved in the negative control of the growth and steroidogenic capacity of the rat Zona Glomerulosa, and suggest that different mechanisms underlie the antiadrenoglomerulotrophic action of these molecules.
Celso E Gomezsanchez - One of the best experts on this subject based on the ideXlab platform.
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disabled 2 is expressed in adrenal Zona Glomerulosa and is involved in aldosterone secretion
Endocrinology, 2007Co-Authors: Damian G Romero, Elise P Gomezsanchez, Licy L Yanes, Angela F De Rodriguez, Maria W Plonczynski, Bronwyn L Welsh, Jane F Reckelhoff, Celso E GomezsanchezAbstract:The differentiation of the adrenal cortex into functionally specific zones is probably due to differential temporal gene expression during fetal growth, development, and adulthood. In our search for adrenal Zona Glomerulosa-specific genes, we found that Disabled-2 (Dab2) is expressed in the Zona Glomerulosa of the rat adrenal gland using a combination of laser capture microdissection, mRNA amplification, cDNA microarray hybridization, and real-time RT-PCR. Dab2 is an alternative spliced mitogen-regulated phosphoprotein with features of an adaptor protein and functions in signal transduction, endocytosis, and tissue morphogenesis during embryonic development. We performed further studies to analyze adrenal Dab2 localization, regulation, and role in aldosterone secretion. We found that Dab2 is expressed in the Zona Glomerulosa and Zona intermedia of the rat adrenal cortex. Low-salt diet treatment increased Dab2-long isoform expression at the mRNA and protein level in the rat adrenal gland, whereas high-salt...
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endothelin 1 stimulation of aldosterone and Zona Glomerulosa ouabain sensitive sodium potassium atpase
The Journal of Steroid Biochemistry and Molecular Biology, 1994Co-Authors: Adali Pecci, Eduardo N Cozza, Maura Devlin, Celso E Gomezsanchez, Elise P GomezsanchezAbstract:Abstract Endothelin stimulates the cells of the Zona Glomerulosa of the adrenal gland and releases aldosterone. While it is a less potent aldosterone secretagogue than angiotensin II endothelin also potentiates the effects of angiotensin II on aldosterone biosynthesis. Two endothelin receptors have been cloned and are expressed in the adrenal Zona Glomerulosa. Intravenous infusion of endothelin at a rate of 80 ng/kg/min for 30 min into rats produced increases in blood pressure, adrenal content of aldosterone and stimulated the ouabain-sensitive sodium potassium ATPase in the Zona Glomerulosa, but not in the Zona fasciculata, of the adrenal. The simultaneous infusion of the isopeptide specific endothelin receptor A (ET A ) antagonist BQ-123 blocked the pressor effects of endothelin, but did not alter the increase in aldosterone content of the Zona Glomerulosa or the ouabain-sensitive sodium potassium ATPase activity. Infusion of Sarafotoxin 6b, an ET B agonist, also increased the aldosterone content of the adrenal and stimulated the ouabain-sensitive sodium potassium ATPase in the Zona Glomerulosa, further indicating that the effect of endothelin is probably mediated by ET B or isopeptide non-specific endothelin receptor. The mechanism by which endothelin stimulates the sodium potassium ATPase is unclear as is the relation between a stimulated sodium potassium ATPase and the potentiation of angiotensin II effect on the adrenal.
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effects of endothelin 1 on its receptor concentration and thymidine incorporation in calf adrenal Zona Glomerulosa cells a comparative study with phorbol esters
Endocrinology, 1990Co-Authors: Eduardo N Cozza, Celso E GomezsanchezAbstract:Endothelin (ET-1) is a 21-amino acid peptide with potent vasopressor and vasoconstrictive properties. Specific, high affinity receptors for ET-1 have been found in the adrenal gland. The stimulation by ET-1 of aldosterone secretion in cultured calf Zona Glomerulosa cells was shown to depend on the serum used for culturing and was not related to the growthpromoting effects of serum or the response to another secretagogue, such as angiotensin-II. In this study, binding of [125I]ET-1 to crude membrane preparations from calf adrenal cortex slices showed that ET-1 binding was greater in the outer slices, corresponding to the Zona Glomerulosa, than in inner slices, corresponding to the Zona fasciculata. ET-1 stimulated aldosterone, but not cortisol, biosynthesis. Adrenal Zona Glomerulosa preincubated with ET-1 resulted in homologous down-regulation. Since ET-1 action involves activation of protein kinase-C (PKC), we studied the effect of a phorbol ester (PMA) on the down-regulation of ET-1 receptors. PMA decrea...
Elise P Gomezsanchez - One of the best experts on this subject based on the ideXlab platform.
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disabled 2 is expressed in adrenal Zona Glomerulosa and is involved in aldosterone secretion
Endocrinology, 2007Co-Authors: Damian G Romero, Elise P Gomezsanchez, Licy L Yanes, Angela F De Rodriguez, Maria W Plonczynski, Bronwyn L Welsh, Jane F Reckelhoff, Celso E GomezsanchezAbstract:The differentiation of the adrenal cortex into functionally specific zones is probably due to differential temporal gene expression during fetal growth, development, and adulthood. In our search for adrenal Zona Glomerulosa-specific genes, we found that Disabled-2 (Dab2) is expressed in the Zona Glomerulosa of the rat adrenal gland using a combination of laser capture microdissection, mRNA amplification, cDNA microarray hybridization, and real-time RT-PCR. Dab2 is an alternative spliced mitogen-regulated phosphoprotein with features of an adaptor protein and functions in signal transduction, endocytosis, and tissue morphogenesis during embryonic development. We performed further studies to analyze adrenal Dab2 localization, regulation, and role in aldosterone secretion. We found that Dab2 is expressed in the Zona Glomerulosa and Zona intermedia of the rat adrenal cortex. Low-salt diet treatment increased Dab2-long isoform expression at the mRNA and protein level in the rat adrenal gland, whereas high-salt...
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endothelin 1 stimulation of aldosterone and Zona Glomerulosa ouabain sensitive sodium potassium atpase
The Journal of Steroid Biochemistry and Molecular Biology, 1994Co-Authors: Adali Pecci, Eduardo N Cozza, Maura Devlin, Celso E Gomezsanchez, Elise P GomezsanchezAbstract:Abstract Endothelin stimulates the cells of the Zona Glomerulosa of the adrenal gland and releases aldosterone. While it is a less potent aldosterone secretagogue than angiotensin II endothelin also potentiates the effects of angiotensin II on aldosterone biosynthesis. Two endothelin receptors have been cloned and are expressed in the adrenal Zona Glomerulosa. Intravenous infusion of endothelin at a rate of 80 ng/kg/min for 30 min into rats produced increases in blood pressure, adrenal content of aldosterone and stimulated the ouabain-sensitive sodium potassium ATPase in the Zona Glomerulosa, but not in the Zona fasciculata, of the adrenal. The simultaneous infusion of the isopeptide specific endothelin receptor A (ET A ) antagonist BQ-123 blocked the pressor effects of endothelin, but did not alter the increase in aldosterone content of the Zona Glomerulosa or the ouabain-sensitive sodium potassium ATPase activity. Infusion of Sarafotoxin 6b, an ET B agonist, also increased the aldosterone content of the adrenal and stimulated the ouabain-sensitive sodium potassium ATPase in the Zona Glomerulosa, further indicating that the effect of endothelin is probably mediated by ET B or isopeptide non-specific endothelin receptor. The mechanism by which endothelin stimulates the sodium potassium ATPase is unclear as is the relation between a stimulated sodium potassium ATPase and the potentiation of angiotensin II effect on the adrenal.
Eduardo N Cozza - One of the best experts on this subject based on the ideXlab platform.
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endothelin 1 stimulation of aldosterone and Zona Glomerulosa ouabain sensitive sodium potassium atpase
The Journal of Steroid Biochemistry and Molecular Biology, 1994Co-Authors: Adali Pecci, Eduardo N Cozza, Maura Devlin, Celso E Gomezsanchez, Elise P GomezsanchezAbstract:Abstract Endothelin stimulates the cells of the Zona Glomerulosa of the adrenal gland and releases aldosterone. While it is a less potent aldosterone secretagogue than angiotensin II endothelin also potentiates the effects of angiotensin II on aldosterone biosynthesis. Two endothelin receptors have been cloned and are expressed in the adrenal Zona Glomerulosa. Intravenous infusion of endothelin at a rate of 80 ng/kg/min for 30 min into rats produced increases in blood pressure, adrenal content of aldosterone and stimulated the ouabain-sensitive sodium potassium ATPase in the Zona Glomerulosa, but not in the Zona fasciculata, of the adrenal. The simultaneous infusion of the isopeptide specific endothelin receptor A (ET A ) antagonist BQ-123 blocked the pressor effects of endothelin, but did not alter the increase in aldosterone content of the Zona Glomerulosa or the ouabain-sensitive sodium potassium ATPase activity. Infusion of Sarafotoxin 6b, an ET B agonist, also increased the aldosterone content of the adrenal and stimulated the ouabain-sensitive sodium potassium ATPase in the Zona Glomerulosa, further indicating that the effect of endothelin is probably mediated by ET B or isopeptide non-specific endothelin receptor. The mechanism by which endothelin stimulates the sodium potassium ATPase is unclear as is the relation between a stimulated sodium potassium ATPase and the potentiation of angiotensin II effect on the adrenal.
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Endothelin-1 stimulation of aldosterone and Zona Glomerulosa ouabain-sensitive sodium/potassium-ATPase.
The Journal of Steroid Biochemistry and Molecular Biology, 1994Co-Authors: Adali Pecci, Eduardo N Cozza, Maura Devlin, Celso E. Gomez-sanchez, Elise P. Gomez-sanchezAbstract:Abstract Endothelin stimulates the cells of the Zona Glomerulosa of the adrenal gland and releases aldosterone. While it is a less potent aldosterone secretagogue than angiotensin II endothelin also potentiates the effects of angiotensin II on aldosterone biosynthesis. Two endothelin receptors have been cloned and are expressed in the adrenal Zona Glomerulosa. Intravenous infusion of endothelin at a rate of 80 ng/kg/min for 30 min into rats produced increases in blood pressure, adrenal content of aldosterone and stimulated the ouabain-sensitive sodium potassium ATPase in the Zona Glomerulosa, but not in the Zona fasciculata, of the adrenal. The simultaneous infusion of the isopeptide specific endothelin receptor A (ET A ) antagonist BQ-123 blocked the pressor effects of endothelin, but did not alter the increase in aldosterone content of the Zona Glomerulosa or the ouabain-sensitive sodium potassium ATPase activity. Infusion of Sarafotoxin 6b, an ET B agonist, also increased the aldosterone content of the adrenal and stimulated the ouabain-sensitive sodium potassium ATPase in the Zona Glomerulosa, further indicating that the effect of endothelin is probably mediated by ET B or isopeptide non-specific endothelin receptor. The mechanism by which endothelin stimulates the sodium potassium ATPase is unclear as is the relation between a stimulated sodium potassium ATPase and the potentiation of angiotensin II effect on the adrenal.
-
effects of endothelin 1 on its receptor concentration and thymidine incorporation in calf adrenal Zona Glomerulosa cells a comparative study with phorbol esters
Endocrinology, 1990Co-Authors: Eduardo N Cozza, Celso E GomezsanchezAbstract:Endothelin (ET-1) is a 21-amino acid peptide with potent vasopressor and vasoconstrictive properties. Specific, high affinity receptors for ET-1 have been found in the adrenal gland. The stimulation by ET-1 of aldosterone secretion in cultured calf Zona Glomerulosa cells was shown to depend on the serum used for culturing and was not related to the growthpromoting effects of serum or the response to another secretagogue, such as angiotensin-II. In this study, binding of [125I]ET-1 to crude membrane preparations from calf adrenal cortex slices showed that ET-1 binding was greater in the outer slices, corresponding to the Zona Glomerulosa, than in inner slices, corresponding to the Zona fasciculata. ET-1 stimulated aldosterone, but not cortisol, biosynthesis. Adrenal Zona Glomerulosa preincubated with ET-1 resulted in homologous down-regulation. Since ET-1 action involves activation of protein kinase-C (PKC), we studied the effect of a phorbol ester (PMA) on the down-regulation of ET-1 receptors. PMA decrea...
