Central and feedback regulation of hypothalamic corticotropin-releasing factor secretion.
Central and feedback regulation of hypothalamic corticotropin-releasing factor secretion.
复制标题
下丘脑促肾上腺皮质激素释放因子分泌的中枢和反馈调节。
DOI：
10.1002/9780470514368.ch4
复制
发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Meaney,MJ
中科院分区：
文献类型：
--
作者：
Plotsky,PM;Thrivikraman,KV;Meaney,MJ
身体、情绪和代谢压力通过多种神经通路激活下丘脑-垂体-肾上腺（HPA）轴。应激诱导的促肾上腺皮质激素（ACTH）分泌的最终下丘脑编码由ACTH促分泌素的差异释放介导。这些包括但不限于促肾上腺皮质激素释放因子（CRF）、精氨酸加压素、催产素和肾上腺素（可能）。在这些物质中，CRF作为该轴的主要调节因子，因为其存在对于本质上较弱的促分泌素的作用是强制性的。由于个体应激源的神经输入编码质量部分利用刺激特异性通路，因此糖皮质激素负反馈在调节HPA轴的持续和后续活动中的有效性取决于应激源的类型和介导初始活动的神经通路的性质。研究表明，对身体压力源（例如出血）的反应对经典的中间反馈具有抵抗力，而对情绪/认知压力源（例如新环境）的反应则对反馈非常敏感。成人机体HPA轴的总体功能特征至少部分是新生儿经验的结果。在成人的差异，下丘脑CRF mRNA水平，中隆起肽含量和垂体对应激反应的新生儿的经验方面。
Physical, emotional and metabolic stressors activate the hypothalamo‐pituitary‐adrenal (HPA) axis via multiple neural pathways. Final hypothalamic coding of stressor‐induced adrenocorticotropic hormone (ACTH) secretion is mediated by differential release of ACTH secretagogues. These include, but may not be limited to, corticotropin‐releasing factor (CRF), arginine vasopressin, oxytocin and, possibly, adrenaline. Among these substances, CRF serves as the predominant regulatory factor of this axis because its presence is obligatory for the action of intrinsically weaker secretagogues. Because neural input‐encoding qualities of individual stressors utilize, in part, stimulus‐specific pathways, the effectiveness of glucocorticoid negative feedback in modulating ongoing and subsequent activity of the HPA axis is dependent upon the type of stressor and the nature of the neural pathways mediating the initial activity. Studies suggest that responses to physical stressors (for example, haemorrhage) are resistant to classical intermediate feedback, whereas those to emotional/cognitive stressors (such as a novel environment) are strongly susceptible to feedback. Overall functional characteristics of the HPA axis in adult organisms are at least partially a result of neonatal experience. In the adult differences in hypothalamic CRF mRNA levels, median eminence peptide content and pituitary responsiveness to stressors can be correlated with aspects of neonatal experience.