ANGIOTENSIN-II RECEPTORS IN PARAVENTRICULAR NUCLEUS, SUBFORNICAL ORGAN, AND PITUITARY-GLAND OF HYPOPHYSECTOMIZED, ADRENALECTOMIZED, AND VASOPRESSIN-DEFICIENT RATS
ANGIOTENSIN-II RECEPTORS IN PARAVENTRICULAR NUCLEUS, SUBFORNICAL ORGAN, AND PITUITARY-GLAND OF HYPOPHYSECTOMIZED, ADRENALECTOMIZED, AND VASOPRESSIN-DEFICIENT RATS
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DOI：
10.1073/pnas.86.2.725
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发表时间：
1989-01-01
影响因子：
11.1
通讯作者：
SAAVEDRA, JM
中科院分区：
文献类型：
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作者：
CASTREN, E;SAAVEDRA, JM
血管紧张素II参与了促肾上腺皮质激素和加压素分泌的调节。血管紧张素II可能直接影响这些激素的分泌，或者通过增加下丘脑室旁核细胞的促肾上腺皮质激素释放激素或加压素的释放来影响这些激素的分泌。脑垂体激素的释放也可能受到血管紧张素II通过穹隆下器官血脑屏障外的受体循环的影响。我们用去垂体、去肾上腺和加压素缺乏的Brattleboro大鼠的血管紧张素II受体的变化作为血管紧张素II在调节促肾上腺皮质激素和加压素分泌中的活性的指标。去肾上腺后，脑室旁核和穹隆下器的血管紧张素受体数量显著减少，而垂体前叶的血管紧张素受体数量不明显，这一作用可被皮质激素逆转。加压素缺乏会减少穹隆下器的血管紧张素受体，增加垂体前叶的血管紧张素受体，但不影响室旁核大细胞或小细胞亚核的血管紧张素II结合。我们的结果提示，血管紧张素II在促肾上腺皮质激素释放激素的分泌调节中可能具有皮质激素依赖性的作用，这在适应应激时皮质酮分泌的增加中可能是重要的。
Angiotensin II has been implicated in the regulation of adrenocorticotropin and vasopressin secretion. Angiotensin II may influence the secretion of these hormones either directly at the pituitary gland or by increasing corticotropin-releasing hormone or vasopressin release from cells that are located in the paraventricular hypothalamic nucleus. Pituitary hormone release may also be influenced by circulating angiotensin II through receptors outside the blood-brain barrier in the subfornical organ. We have used alterations in angiotensin II receptors in hypophysectomized, adrenalectomized, and vasopressin-deficient Brattleboro rats as indicators of the activity of angiotensin II in the regulation of adrenocorticotropin and vasopressin secretion. Angiotensin receptor number in the paraventricular nucleus and the subfornical organ, but not in the anterior pituitary gland, was significantly decreased by adrenalectomy, and this effect was reversed by corticoids. Vasopressin deficiency decreased angiotensin receptors in the subfornical organ and increased them in the anterior pituitary gland but did not affect angiotensin II binding in either magnocellular or parvocellular subnucleus of the paraventricular nucleus. Our results suggest that angiotensin II may have a corticoid-dependent role in the regulation of corticotropin-releasing hormone secretion, which could be important in the adaptation to elevated corticosterone secretion in stress.