神经肽Y增强去甲肾上腺素对视上核神经分泌细胞的兴奋作用。

Neuropeptide Y potentiates excitation of supraoptic neurosecretory cells by noradrenaline.

作者信息

Sibbald J R, Wilson B K, Day T A

机构信息

Department of Physiology, University of Otago Medical School, Dunedin, New Zealand.

出版信息

Brain Res. 1989 Oct 9;499(1):164-8. doi: 10.1016/0006-8993(89)91147-5.

DOI:10.1016/0006-8993(89)91147-5

PMID:2804665

Abstract

The effects of neuropeptide Y (NPY) and noradrenaline (NA) on the activity of rat supraoptic nucleus (SON) neurosecretory cells were examined using perfused hypothalamic slices. Bath application of either NPY (10(-9)-10(-6) M) or NA (10(-6)-10(-3) M) excited SON cells, although only NA elicited consistent, dose-dependent effects. Application of NPY at a dose having virtually no direct effects (10(-8) M) produced a 5-fold increase in SON cell responsiveness to NA at the sub-maximal response dose of 10(-5) M, but did not alter the minimum concentration of NA required to excite SON cells or increase the maximal response elicited by higher NA concentrations. The effects of NA, alone or in combination with NPY, were abolished by alpha-adrenoreceptor blockade. These data suggest that NPY has only weak direct effects on neurosecretory cells, but may have important neuromodulatory actions, significantly enhancing the excitatory effects of NA.

摘要

使用灌流的下丘脑切片研究了神经肽Y（NPY）和去甲肾上腺素（NA）对大鼠视上核（SON）神经分泌细胞活性的影响。浴槽中加入NPY（10^(-9)-10^(-6)M）或NA（10^(-6)-10^(-3)M）均可兴奋SON细胞，不过只有NA能产生持续的剂量依赖性效应。以几乎无直接作用的剂量（10^(-8)M）应用NPY，在亚最大反应剂量10^(-5)M时，SON细胞对NA的反应性增加了5倍，但并未改变兴奋SON细胞所需的NA最低浓度，也未增加更高NA浓度所引发的最大反应。单独使用NA或与NPY联合使用时，其效应均被α-肾上腺素能受体阻断所消除。这些数据表明，NPY对神经分泌细胞只有微弱的直接作用，但可能具有重要的神经调节作用，可显著增强NA的兴奋作用。