Studies on Hypothalamic CRHmRNA

下丘脑CRHmRNA的研究

基本信息

批准号：
63570536
负责人：
HASHIMOTO Kozo
金额：
$ 1.28万
依托单位：
Okayama University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1990
项目状态：
已结题

项目摘要

Corticotropin Releasing hormone (CRH) and Arginine Vaso-Pressin (AVP) are the most important physiological ACTH releasing factors. Gene expression of CRHmRNA and AVPmRNA were investigated. Levels of AVPmRNA in the hypothalamic Supra-Optic Nucleus (SON) and the Para-Ventricular Nucleus (PVN) were determined by semiquantitative in situ hybridization histochemistry. However, we failed to detect CRHmRNA levels by in situ hybridization technique in spite of great efforts.In bilaterally adrenalectomized rats, plasma ACTH levels increased significantly, CRH levels in the Median Eminence (ME) decreased and AVP levels in the ME increased one week after surgery. AVPmRNA in the PVN and SON increased significantly.In the rats given hypertonic saline (2%) for 3 days, CRH levels in the PVN and ME did not differ from those in the control rats. Plasma corticosterone, and AVP increased significantly. AVP contents in the posterior pituitary decreased and AVPmRNA in the PVN and SON increased significantly.Water deprivation increased AVPmRNA in the PVN and SON. Plasma levels of ACTH, corticosterone, AVP and osmolality were significantly elevated. The concentration in the posterior pituitary, ME and the remaining hypothalamic tissue did not differ significantly.Food deprivation decreased AVPmRNA in the PVN and SON. Plasma levels of ACTH and corticosterone were greatly elevated, while plasma AVP and osmolality did not differ significantly. The results indicated that food deprivation stimulated the pituitaryadrenal axis and that a reduction in AVPmRNA levels in food deprived rats was caused by food deprivation per se.According to these observations, AVP may be at least partly responsible for ACTH elevation in adrenal insufficiency, hypertonic saline administration and water deprivation but not in food deprivation.

皮质激素释放激素（CRH）和精氨酸血管蛋白（AVP）是最重要的生理ACTH释放因子。研究了CRHMRNA和AVPMRNA的基因表达。下丘脑上核核（SON）和室室核（PVN）中的AVPMRNA水平通过半定位原位杂交组织化学确定。然而，尽管付出了很大的努力，但我们无法通过原位杂交技术检测到CRHMRNA水平。在双侧肾上腺切除大鼠中，血浆ACTH水平显着升高，ME在手术后ME的中位数隆起水平（ME）的CRH水平降低，而AVP水平却降低了。 PVN中的AVPMRNA显着增加。在给予高渗盐水（2％）3天的大鼠中，PVN中的CRH水平与对照大鼠中的CRH水平没有差异。血浆皮质酮和AVP显着增加。垂体后垂体中的AVP含量降低，PVN中的AVPMRNA显着增加。剥夺PVN和SON中的AVPMRNA增加。血浆ACTH，皮质酮，AVP和渗透压的水平显着升高。垂体后，ME和剩余的下丘脑组织的浓度没有显着差异。食物剥夺降低了PVN和SON的AVPMRNA。 ACTH和皮质酮的血浆水平升高，而血浆AVP和渗透压没有显着差异。结果表明，食物剥夺刺激了垂体性肾上腺轴，并且剥夺大鼠食物中的AVPMRNA水平降低是由食物剥夺本身引起的。根据这些观察结果，AVP至少可以部分造成肾上腺不足，高含量盐水丧失和水的肾上腺剥夺，而不是食物中的ACTH升高。