肾上腺切除术对促肾上腺皮质激素释放激素调节促肾上腺皮质激素释放的影响：腺苷酸环化酶活性、环磷酸腺苷依赖性蛋白激酶活性及促肾上腺皮质激素释放

Effects of adrenalectomy on CRH regulation of ACTH release: adenylate cyclase activity, cyclic AMP-dependent protein kinase activity and ACTH release.

作者信息

Dhillon G S, Oleshansky M A, Kant G J

机构信息

Department of Medical Neurosciences, Walter Reed Army Institute of Research, Washington, D.C. 20307-5100.

出版信息

Cell Signal. 1989;1(3):295-301. doi: 10.1016/0898-6568(89)90047-8.

DOI:10.1016/0898-6568(89)90047-8

PMID:2561946

Abstract

Corticotropin releasing hormone (CRH) stimulation of ACTH release and cyclic AMP-mediated events involved in the control of ACTH release were compared in sham-operated and adrenalectomized rats. CRH-stimulated adenylate cyclase activity was decreased in pituitary homogenates from adrenalectomized animals. CRH-stimulated cyclic AMP accumulation was essentially abolished and CRH-stimulated cyclic AMP-dependent protein kinase (A-kinase) activity was decreased in freshly prepared anterior pituitary cells from adrenalectomized animals. Basal and CRH-stimulated ACTH release was elevated in these cells. Since ACTH release is increased in adrenalectomized rats despite the down regulation of CRH-linked pituitary mechanisms, we speculate that the site of action of disinhibition by corticosterone of ACTH release (or synthesis) following adrenalectomy is distal to the generation of cyclic AMP and/or that non-CRH mediated mechanisms assume a greater role in ACTH regulation following adrenalectomy.

摘要

在假手术组和肾上腺切除大鼠中，比较了促肾上腺皮质激素释放激素（CRH）对促肾上腺皮质激素（ACTH）释放的刺激作用以及参与ACTH释放调控的环磷酸腺苷（cAMP）介导的事件。肾上腺切除动物的垂体匀浆中，CRH刺激的腺苷酸环化酶活性降低。在肾上腺切除动物新鲜制备的垂体前叶细胞中，CRH刺激的cAMP积累基本被消除，且CRH刺激的cAMP依赖性蛋白激酶（A激酶）活性降低。这些细胞中基础ACTH释放和CRH刺激的ACTH释放均升高。由于肾上腺切除大鼠中ACTH释放增加，尽管与CRH相关的垂体机制下调，我们推测肾上腺切除后皮质酮对ACTH释放（或合成）去抑制作用的作用位点在cAMP产生的远端，和/或非CRH介导的机制在肾上腺切除后的ACTH调节中发挥更大作用。