MICROINJECTION OF NOREPINEPHRINE INTO THE PARAVENTRICULAR NUCLEUS OF THE HYPOTHALAMUS STIMULATES CORTICOTROPIN-RELEASING FACTOR GENE-EXPRESSION IN CONSCIOUS RATS
MICROINJECTION OF NOREPINEPHRINE INTO THE PARAVENTRICULAR NUCLEUS OF THE HYPOTHALAMUS STIMULATES CORTICOTROPIN-RELEASING FACTOR GENE-EXPRESSION IN CONSCIOUS RATS
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DOI：
10.1210/en.135.5.2177
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发表时间：
1994-11-01
期刊：
影响因子：
4.8
通讯作者：
DEMURA, H
中科院分区：
文献类型：
--
作者：
ITOI, K;SUDA, T;DEMURA, H
为探讨下丘脑室旁核（PVH）内去甲肾上腺素（NE）对CRF基因表达和释放的生理效应，将NE微量注射到清醒大鼠PVH内，动态观察了垂体前叶（AP）内POMC mRNA、下丘脑含PVH片段内CRF mRNA和血浆ACTH的水平。通过向PVH中注射NE（5-50 nmol/侧），血浆ACTH水平呈剂量依赖性增加。NE注射后90 min，AP中POMC mRNA水平和下丘脑CRFmRNA水平明显升高，120 min后进一步升高，NE剂量依赖性地增加AP中POMC mRNA水平和下丘脑CRFmRNA水平侧脑室注射哌唑嗪可完全阻断下丘脑NE注射后血浆ACTH水平的升高，而普萘洛尔则无明显作用。这些结果表明，NE刺激CRF基因表达的PVH和CRF分泌到门静脉循环，从而积极调节下丘脑-垂体-肾上腺轴。α（1）-肾上腺素能受体可能介导NE对CRF神经元的作用。
To examine the physiological effects of norepinephrine (NE) in the paraventricular nucleus of the hypothalamus (PVH) on CRF gene expression and CRF release, NE was microinjected bilaterally into the PVH of conscious rats, and kinetic studies were performed on the levels of POMC messenger RNA (mRNA) in the anterior pituitary (AP), CRF mRNA in the PVH-containing hypothalamic fragment, and plasma ACTH. Plasma ACTH levels were increased dose dependently by NE (5-50 nmol/side) injection into the PVH. They reached their peaks after 30 min and returned to the basal values after 90 min. The POMC mRNA level in the AP and hypothalamic CRF mRNA level increased significantly 90 min after NE injection and increased further after 120 min. The POMC mRNA level in the AP and hypothalamic CRF mRNA level were increased dose dependently by NE (5-50 nmol/ side) after 120 min. Intracerebroventricular pretreatment with prazosin abolished completely the increase in plasma ACTH levels after intrahypothalamic NE injection, whereas pretreatment with propranolol was without significant effect. These results suggest that NE stimulates CRF gene expression in the PVH and CRF secretion into the portal circulation, thus regulating positively the hypothalamic-pituitary-adrenal axis. alpha(1)-Adrenergic receptors may mediate the action of NE on CRF neurons.