In vivo regulation of the steroidogenic activity of rat luteal cells by insulin

doi:10.1016/0960-0760(94)00182-L

The Journal of Steroid Biochemistry and Molecular Biology

Volume 52, Issue 4, April 1995, Pages 329-335

https://doi.org/10.1016/0960-0760(94)00182-L Get rights and content

Abstract

The aim of the present study was to determine the long-term effects of insulin treatment on luteal cell function. For this purpose, superovulated prepubertal rats were treated with insulin (group I) or vehicle (group C) for 9 days. Serum progesterone (P₄) levels were increased in the insulin-treated group (55 ± 10 vs 134 ± 31 ng/ml, P < 0.05). Isolated luteal cells were incubated 3 h, and P₄ and 20α-hydroxy-progesterone (20α-OH-P) were measured in the incubation media. A decrease in P₄ levels and an increase in 20α-OH-P values [P₄ (ng/ml): C = 26.6 ± 0.3; I = 20 ± 2; 20α-OH-P (ng/ml): C = 62 ± 2; I: 120 ± 7; P < 0.01] were observed in group I. In addition, progestagen (P₄ + 20α-OH-P) levels were higher in group I (C = 88 ± 2; I = 140 ± 9 ng/ml; P < 0.001). When cytochrome P450_SCC contents were measured by immunoblotting, a marked increase was observed in luteal cells obtained from group I. LH receptor numbers were decreased in luteal cells isolated from group I (C = 388,834 ± 14,146; I = 303,057 ± 13,392 sites/cell; P < 0.001) with a concomitantly diminished LH responsiveness. It is concluded that in vivo treatment of superovulated rats with insulin increases luteal progestagen production by increasing the content of cytochrome P450_SCC.

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PaperIn vivo regulation of the steroidogenic activity of rat luteal cells by insulin

Abstract

Am. J. Obstet. Gynecol.

Molec. Cell. Endocrinol.

Fertil. Steril.

Molec. Cell. Endocrinol.

J. Steroid Biochem.

J. Biol. Chem.

Molec. Cell. Endocrinol.

Molec. Cell. Endocrinol.

J. Biol. Chem.

Fertil. Steril.

J. Biol. Chem.

J. Biol. Chem.

J. Biol. Chem.

Int. Rev. Cytol.

Molec. Cell. Endocrinol.

J. Biol. Chem.

On the paradox of insulin-induced hyperandrogenism in insulin-resistant states

Endocr. Rev.

Cellular mechanisms of insulin resistance in polycystic ovarian syndrome

J. Clin. Endocrinol. Metab.

The role of hyperinsulinemia in the pathogenesis of ovarian hyperandrogenism

Fertil. Steril.

The gonadotropic function of insulin

Endocrine Rev.

A novel role for somatomedin-C in the cytodifferentiation of the ovarian granulosa cell

Endocrinology

Insulin resistance associated with androgen excess in women with auto-antibodies to the insulin receptor

Ann. Int. Med.

Somatomedin-C synergizes with follicle-stimulating hormone in the acquisition of progestin biosynthetic capacity by cultured rat granulosa cells

Endocrinology

Mechanisms subserving the trophic actions of insulin on ovarian cells: in vitro studies using swine granulosa cells

J. Clin. Invest.

Paper
In vivo regulation of the steroidogenic activity of rat luteal cells by insulin