The aim of this study was to evaluate the effects of rat atrial-peptide type II (rAP-II) on testicular steroidogenesis by isolated adult rat Leydig cells. rAP-II stimulates testosterone secretion. The maximal stimulatory effects of rAP-II on testosterone production occurred at the dose of 10-11 M. At the same dose this peptide stimulates androstenedione and dehydroepiandrosterone-sulphate production, two important testosterone precursors of delta-4 and delta-5 steroidogenetic pathways, respectively. At higher doses, 10-9 and 10-7 M, the stimulatory effect of rAP-II on testosterone secretion is strongly declined, on androstenedione secretion is abolished, whereas on dehydroepiandrosterone-sulphate secretion remains unaffected. These data suggest that rAP-II at low doses exerts a stimulatory effect on the early steroidogenetic step by isolated adult rat Leydig cells. At higher doses this peptide seems to influence the testicular steroidogenesis, probably exerting a limiting reaction step involving the 3-βOH-steroid-dehydrogenase activity. © 1988 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.
Effects of atrial natriuretic factor (ANF) on rat testicular steroidogenesis in vitro.
FORESTA, CARLO;
1988
Abstract
The aim of this study was to evaluate the effects of rat atrial-peptide type II (rAP-II) on testicular steroidogenesis by isolated adult rat Leydig cells. rAP-II stimulates testosterone secretion. The maximal stimulatory effects of rAP-II on testosterone production occurred at the dose of 10-11 M. At the same dose this peptide stimulates androstenedione and dehydroepiandrosterone-sulphate production, two important testosterone precursors of delta-4 and delta-5 steroidogenetic pathways, respectively. At higher doses, 10-9 and 10-7 M, the stimulatory effect of rAP-II on testosterone secretion is strongly declined, on androstenedione secretion is abolished, whereas on dehydroepiandrosterone-sulphate secretion remains unaffected. These data suggest that rAP-II at low doses exerts a stimulatory effect on the early steroidogenetic step by isolated adult rat Leydig cells. At higher doses this peptide seems to influence the testicular steroidogenesis, probably exerting a limiting reaction step involving the 3-βOH-steroid-dehydrogenase activity. © 1988 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.Pubblicazioni consigliate
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