Role of glucocorticoids in the stress-induced suppression of testicular steroidogenesis in adult male rats

doi:10.1016/0018-506X(92)90005-G

Hormones and Behavior

Volume 26, Issue 3, September 1992, Pages 350-363

https://doi.org/10.1016/0018-506X(92)90005-G Get rights and content

Abstract

We have examined the role of glucocorticoids in the stress-induced inhibition of testicular steroidogenesis. Immobilization (3 hr) reduced plasma testosterone (T) levels to 24% of control values but did not affect plasma LH levels. This reduction was partially reversed by in vivo injections of the antiglucocorticoid, RU486, prior to the stress session at a dose of 10 mg/kg BW, but not at 1.0 or 50 mg/kg BW. Stressed rats that were treated with 10 mg/kg BW RU486 had twofold higher plasma T levels than vehicle-treated stressed animals. Injections of RU486 did not affect plasma LH levels in control or stressed rats and did not affect T levels of unstressed rats. Stressed rats had eightfold higher plasma corticosterone levels than controls, and RU486 had no effect on control or stress levels of corticosterone. The possible role of glucocorticoids in mediating the effect of stress on testicular T production was investigated also in vitro by incubating testicular interstitial cells from unstressed rats for 3 hr with corticosterone (0, 0.01, 0.1, or 1.0 μM) or dexamethasone (0, 0.001, 0.01, or 0.1 μM), followed by an additional 2 hr with hCG (0, 25, 50, or 100 μIU). Both corticosterone and dexamethasone inhibited hCG-stimulated T production in a dose-dependent manner. Cells incubated with the highest concentration of either of the glucocorticoids showed significantly reduced responses to hCG stimulation. In the absence of hCG, in vitro T production was not affected by dexamethasone or 0.01 and 0.1 μM corticosterone. However, the highest dose of corticosterone (1.0 μM) produced a 63% elevation in basal T production. Coincubation of testicular interstitial cells with corticosterone (1.0 μM) or dexamethasone (0.1 μM) and RU486 (0.01, 0.1, and 1.0 μM) reversed the glucocorticoid-induced suppressions of T production in a dose-dependent manner. Our results suggest that during stress increases in plasma levels of glucocorticoids in male rats act via glucocorticoid receptors on testicular interstitial cells to suppress the testicular response to gonadotropins, and that the decline of testosterone production during immobilization stress is in part mediated by a direct action of glucocorticoids on the testis.

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¹: Current address: Research Service (151), VA Medical Center, Downtown Division, 1 Freedom Way, Augusta, GA 30910.

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Role of glucocorticoids in the stress-induced suppression of testicular steroidogenesis in adult male rats

Abstract

J. Steroid Biochem.

Mol. Cell. Endocrinol.

Exp. Cell Res.

Horm. Behav.

Psychoneuroendocrinology

Horm. Behav.

Effect of opioid antagonists on testosterone secretion by purified Leydig cells

Direct inhibitory effect of glucocorticoids upon testicular luteinizing hormone receptor and steroidogenesis in vivo and in vitro

Endocrinology

The neuroendocrinology of male reproduction

Stress-induced testicular hyposensitivity to gonadotropin in rats: Role of the pituitary gland

Biol. Reprod.

Effects of chronic intermittent immobilization stress on rat testicular androgenic function

Endocrinology

Serum LH and FSH following passive immunization against circulating testosterone in the intact male rat and in orchidectomized rats bearing subcutaneous silastic implants of testosterone

Arch. Androl.

Levels of adrenal and gonadal hormones in rhesus monkeys during chronic hypokinesia

Endocrinology

Disorders of the testis and the male reproductive tract

Graded footshock stress elevates pituitary cyclic AMP and plasma β-endorphin, β-LPH, corticosterone and prolactin

Life Sci.

Effect of luteinizing hormone deprivation in situ on steroidogenesis of rat Leydig cells purified by a multistep procedure

Biol. Reprod.

The endocrine effects of longterm treatment with mifepristone (RU486)

J. Clin. Endocrinol. Metab.

Glucocorticoid antagonists and the role of glucocorticoids at the resting and stress state

Adv. Exp. Med. Biol.