VASOPRESSIN-CRF-ACTH INTERACTIONS IN CONSCIOUS STATE

本研究将探讨神经垂体的作用， 加压素在控制ACTH和皮质醇分泌中的作用， 促肾上腺皮质激素释放因子（CRF）在控制 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 低血压和减弱皮质醇对绵羊CRF的反应- 促肾上腺皮质激素增加。 促肾上腺皮质激素和皮质醇对 硝普钠诱导的血压钳性下降， 外源性绵羊CRF输注将在完整的狗中测定， 神经垂体切除犬持续加压素 替换，以及在没有神经垂体切除的狗中 加压素替代（尿崩症）。 这将决定 如果ACTH对低血压的反应减弱， 皮质醇对CRF诱导的ACTH增加的反应 切除神经垂体的狗可以通过以下方法恢复正常 减轻尿崩症的症状。 急性输注 垂体后叶素在神经垂体切除犬低血压期间， 在完整犬中观察到的加压素水平升高将 以确定是否对低血压有完全的ACTH反应 需要大量增加血浆加压素。 此外，本发明还提供了一种方法， 外源性ACTH输注将用于直接评估 加压素在肾上腺皮质敏感性（皮质醇，醛固酮， 和肾上腺雄激素）。 已经提出，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 加压素对低血压和/或高渗的反应将 在有意识的狗身上。 将对犬进行以下预处理： 血浆皮质醇的生理性增加以及随后的 加压素对硝普钠和/或高渗盐水的反应将 进行评估。 自从CRF的排序和合成以来， CRF和加压素相互作用有很多。 研究 本文提出的将检查神经垂体的作用， 加压素，CRF和类固醇反馈在控制 垂体前叶和垂体后叶以及肾上腺皮质。

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.