VASOPRESSIN-CRF-ACTH INTERACTIONS IN CONSCIOUS STATE

本研究将探讨神经垂体素的作用。 加压素对促肾上腺皮质激素和皮质醇分泌的控制作用 促肾上腺皮质激素释放因子(CRF)在控制高血压病中的作用 清醒犬血管加压素和促肾上腺皮质激素分泌。 神经垂体切除术减弱ACTH对 降压和减弱皮质醇对绵羊CRF的反应- 诱导ACTH升高。促肾上腺皮质激素和皮质醇对 硝普钠引起的钳夹效应降低血压和 外源性绵羊促肾上腺皮质激素释放因子的输注将在完整的狗身上确定， 持续应用加压素的神经下垂切除犬 替换，并在没有神经功能低下的狗身上 加压素替代疗法(尿崩症)。这将决定 IF减弱ACTH对低血压的反应和减弱 促肾上腺皮质激素释放激素诱导的皮质醇反应增强 神经垂体切除犬可通过以下方法恢复正常 缓解尿崩症的症状。急性输注阿司匹林 神经垂体切除犬低血压过程中的加压素 在完好无损的狗身上观察到的加压素水平升高 以确定ACTH对低血压的全部反应 需要大幅增加血浆中的加压素。此外, 外源性ACTH输注将用于直接评估其作用 加压素对肾上腺皮质的敏感性(皮质醇、醛固酮、 和肾上腺雄激素)。 已有研究表明，血浆加压素对 渗透性和非渗透性刺激对糖皮质激素敏感 负反馈抑制。糖皮质激素敏感性的研究 加压素对低血压和/或高渗透压的反应 在清醒的狗身上下定决心。狗将会被预先处理 血浆皮质醇的生理性增加以及随后的 加压素对硝普钠和/或高渗盐水的反应 被评估。 自从CRF的测序和合成以来，对CRF的研究 CRF和加压素的相互作用是多方面的。这些研究 在这里提出的将研究神经垂体的作用， 加压素、促肾上腺皮质激素释放因子和类固醇反馈在控制高血压中的作用 前后垂体腺和肾上腺皮质。

This study will investigate the role of neurohypophyseal vasopressin in the control of ACTH and cortisol secretion and the role of corticotropin-releasing factor (CRF) in the control of vasopressin and ACTH secretion in conscious dogs. Neurohypophysectomy attenuates the ACTH response to hypotension and attenuates the cortisol response to ovine CRF- induced increases in ACTH. The ACTH and cortisol response to nitroprusside-induced clamped decreases in blood pressure and to exogenous ovine CRF infusions will be determined in intact dogs, neurohyupophysectomized dogs with continuous vasopressin replacement, and in neurohypophsectomized dogs without vasopressin replacement (diabetes insipidus). This will determine if attenuated ACTH responses to hypotension and attenuated cortisol responses to CRF-induced increased in ACTH In neurohypophysectomized dogs can be restored to normal by alleviating the symptoms of diabetes insipidus. Acute infusions of vasopressin during hypotension in neurohypophysectomized dogs to elevate vasopressin levels observed in intact dogs will be performed to determine if the full ACTH response to hypotension requires large increases in plasma vasopressin. In addition, exogenous ACTH infusions will be used to directly assess the role of vasopressin in adrenocortical sensitivity (cortisol, aldosterone, and adrenal androgen) in conscious dogs. It has been suggested that the plasma vasopressin response to osmotic and non-osmotic stimuli are sensitive to glucocorticoid negative feedback inhibition. The glucocorticoid sensitivity of vasopressin responses to hypotension and/or hyperosmolality will be determined in conscious dogs. Dogs will be pretreated with physiological increases in plasma cortisol and the subsequent vasopressin response to nitroprusside and/or hypertonic saline will be assessed. Since the sequencing and synthesis of CRF, studies of the interaction of CRF and vasopressin have been many. The studies proposed herein will examine the role of the neurohypophysis, vasopressin, CRF, and steroid feedback in the control of the anterior and posterior pituitary and the adrenal cortex.