El Fazaa S, Gharbi N, Kamoun A, Somody L
Département de Biologie, Faculté des Sciences, Tunis, Tunisia.
Comp Biochem Physiol C Toxicol Pharmacol. 2000 Jun;126(2):129-37. doi: 10.1016/s0742-8413(00)00105-5.
In the present study, we have examined in Wistar rats the effects of food or water deprivation of 3 days on the hypophyso-adrenal axis, vasopressinergic system and activity of A1 noradrenergic brain stem cell group, which is involved in the control of the hypothalamic neuro-endocrine activity. Levels of adrenocorticotropic hormone (ACTH) and vasopressin (AVP) were determined by radio-immunoassay, and corticosterone level was determined by fluorimetric method. Plasma levels of ACTH and corticosterone were greatly increased in both groups of rats. In water-deprived rats, plasma AVP (13.83 +/- 1.63 vs. 3.03 +/- 0.23 pg/ml) and osmolality levels were significantly elevated with a marked decrease of AVP hypophysis content (272 +/- 65 vs. 1098 +/- 75 ng/mg protein), but not in food-deprived rats in which osmolality did not change and AVP remained stocked (2082 +/- 216 ng/mg protein) in the hypophysis without release in the plasma (1.11 +/- 0.23 pg/ml). These observations indicated that both food-deprivation and water-deprivation stimulated the pituitary adrenal axis thereby suggesting a stress state. AVP production is stimulated both by fluid and food restriction but is secreted with differential effects: during food restriction AVP secretion is limited to supporting the hypothalamic pituitary-adrenal system.
在本研究中，我们检测了Wistar大鼠3天食物或水剥夺对垂体 - 肾上腺轴、血管加压素能系统以及参与下丘脑神经内分泌活动控制的A1去甲肾上腺素能脑干细胞群活性的影响。采用放射免疫分析法测定促肾上腺皮质激素（ACTH）和血管加压素（AVP）水平，采用荧光法测定皮质酮水平。两组大鼠血浆ACTH和皮质酮水平均显著升高。在缺水大鼠中，血浆AVP（13.83±1.63对3.03±0.23 pg/ml）和渗透压水平显著升高，垂体AVP含量显著降低（272±65对1098±75 ng/mg蛋白），但在缺食大鼠中，渗透压未改变，AVP仍储存在垂体中（2082±216 ng/mg蛋白），未释放到血浆中（1.11±0.23 pg/ml）。这些观察结果表明，食物剥夺和水剥夺均刺激垂体 - 肾上腺轴，从而提示处于应激状态。液体和食物限制均刺激AVP产生，但分泌效果不同：在食物限制期间，AVP分泌仅限于支持下丘脑 - 垂体 - 肾上腺系统。
