Hypothalamic Pituitary Adrenal Axis and Hypothalamic–Neurohypophyseal Responsiveness in Water-Deprived Rats
Hypothalamic Pituitary Adrenal Axis and Hypothalamic–Neurohypophyseal Responsiveness in Water-Deprived Rats
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缺水大鼠的下丘脑垂体肾上腺轴和下丘脑-神经垂体反应性
作者：
V. Grinevich;Xin;J. Verbalis;G. Aguilera
通过分析促肾上腺皮质激素释放激素（CRH）和抗利尿激素（VP）表达的差异，研究了渗透刺激对大细胞和小细胞下丘脑神经元的影响。缺水降低了CRH mRNA的基础水平，但在4小时的限制或6小时的脂多糖（LPS）注射后的增量与对照组相似。相反，水分剥夺对副细胞神经元中基础VP异核RNA （hnRNA）和mRNA水平没有影响，但抑制或LPS注射的反应降低。缺水大鼠大细胞室旁核、视上核、血浆钠和抗利尿激素的VP表达较高，且不受抑制。LPS注射降低了大细胞神经元VP mRNA而非hnRNA水平，并增加了血浆加压素水平，这与血浆钠的变化无关。这伴随着垂体后叶加压素mRNA含量的增加。数据表明，慢性渗透刺激时ACTH对急性应激反应的减弱与细细胞神经元不能增加VP而不是CRH表达有关。此外，lps诱导的内毒素血症会引起大细胞血管加压能系统的紊乱，并意想不到地增强渗透模拟VP分泌。LPS后VP转录不增加，VP mRNA分布改变，提示内毒素血症影响神经垂体轴突末端水平的分泌过程。
The differential effects of osmotic stimulation on magnocellular and parvocellular hypothalamic neurons were studied by analysis of corticotropin-releasing hormone (CRH) and vasopressin (VP) expression in controls and 48-h water-deprived rats subjected to either restraint for 1 h or a single lipopolysaccharide injection (250 microg/100 g). Water deprivation reduced basal CRH mRNA levels but the increments following 4 h of restraint or 6 h lipopolysaccharide (LPS) injection were similar to those in controls. In contrast, water deprivation had no effect on basal VP heteronuclear RNA (hnRNA) and mRNA levels in parvocellular neurons, but responses to restraint or LPS injection were reduced. VP expression in magnocellular paraventricular and supraoptic nuclei, and plasma sodium and vasopressin were higher in water-deprived rats, changes which were unaffected by restraint. LPS injection reduced VP mRNA but not hnRNA levels in magnocellular neurons and increased plasma vasopressin levels only in water-deprived rats independently of changes in plasma sodium. This was accompanied by an increase in vasopressin mRNA content in the posterior pituitary. The data show that the blunted ACTH responses to acute stress during chronic osmotic stimulation are correlated with the inability of parvocellular neurons to increase VP rather than CRH expression. In addition, LPS-induced endotoxemia causes disturbances of the magnocellular vasopressinergic system with an unexpected potentiation of osmotic simulated VP secretion. The lack of increase in VP transcription after LPS and changes in VP mRNA distribution suggest that endotoxemia affect the secretory process at the levels of the neurohypophyseal axon terminal.
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慢性低钠血症对大鼠中枢和外周催产素和加压素分泌的影响。
影响因子：
4.1
作者：
Iványi,T;Dohanics,J;Verbalis,JG
通讯作者：
Verbalis,JG
糖皮质激素对促肾上腺皮质激素释放激素和加压素转录的差异调节。
影响因子：
4.8
作者：
Ma,XM;Aguilera,G
通讯作者：
Aguilera,G
DOI：
10.1073/pnas.90.19.8967
发表时间：
1993-10-01
影响因子：
11.1
作者：
CHEN, RP;LEWIS, KA;VALE, WW
通讯作者：
VALE, WW
低钠血症诱导的大细胞神经元抑制导致大鼠受刺激的促肾上腺皮质激素分泌的应激选择性损害。
影响因子：
4.8
作者：
Dohanics,J;Hoffman,GE;Verbalis,JG
通讯作者：
Verbalis,JG