肾上腺切除术和糖皮质激素受体拮抗剂RU38486对大鼠垂体生长激素释放激素受体基因表达的影响

Effects of adrenalectomy and glucocorticoid receptor antagonist, RU38486, on pituitary growth hormone-releasing hormone receptor gene expression in rats.

作者信息

Ohyama T, Sato M, Ohye H, Murao K, Niimi M, Takahara J

机构信息

First Department of Internal Medicine, Kagawa Medical University, Japan.

出版信息

Peptides. 1998;19(6):1063-7. doi: 10.1016/s0196-9781(97)00472-5.

DOI:10.1016/s0196-9781(97)00472-5

PMID:9700756

Abstract

We examined the effects of adrenalectomy and a glucocorticoid receptor antagonist, RU38486, on pituitary GH-releasing hormone (GRH) receptor gene expression in rats. GRH receptor mRNA levels were significantly decreased in adrenalectomized rats and replacement of dexamethasone reversed the decrease to normal. GH secretion was inhibited by adrenalectomy, whereas dexamethasone replacement failed to restore the impaired GH secretion. A high dose of RU38486 had an agonistic effect on GRH receptor mRNA levels. These results suggest that endogenous glucocorticoid is necessary for normal expression of pituitary GRH receptor mRNA in rats.

摘要

我们研究了肾上腺切除术及一种糖皮质激素受体拮抗剂RU38486对大鼠垂体生长激素释放激素（GRH）受体基因表达的影响。肾上腺切除大鼠的GRH受体mRNA水平显著降低，而地塞米松替代可将降低水平逆转至正常。肾上腺切除术抑制了生长激素（GH）分泌，而地塞米松替代未能恢复受损的GH分泌。高剂量的RU38486对GRH受体mRNA水平具有激动作用。这些结果表明，内源性糖皮质激素对于大鼠垂体GRH受体mRNA的正常表达是必需的。