大鼠下丘脑催产素样和加压素样神经元与5-羟色胺及儿茶酚胺能传入纤维末梢的关系

用免疫组织化学ABC双标记法,显示下丘脑各神经分泌核区中催产素样免疫反应(oxytocin-like immunoreactivity,OT-li)、加压素样免疫反应(vasopressin-like immunoreaetivity,VP-li神经元及5-羟色胺样免疫反应(serotonin-like immunoreactivity,5-HT-li)和儿茶酚胺能,即酪胺酸羟化酶免疫反应(tyrosine hydroxylase-like immunoractivity,TH-li)纤维末梢,对这两种单胺能纤维末梢在视上核、室旁核及各种神经分泌副核中的分布,及其与OT-li和VP-li神经元相关的特点及异同加以分析。结果显示,5-HT-li与TH-li纤维末梢在下丘脑视上核、室旁核及各神经分泌副核中,与OT-li及VP-li神经元相接触的多寡程度多不相同。视上核、室旁核内有极高密度的TH-li纤维末梢,与OT-li及VP-li神经元相接触,并在多数神经分泌副核的OT-li及Vp-li神经元周围,也有多寡不等的分布;而中等至高密度的5-HT-li纤维末梢,主要与各神经分泌副核内的OT-li或VP-li神经元相接触。说明5-HT-li和儿茶酚胺能传入纤维末梢,可能分别侧重调控不同神经分泌核区的大细胞神经分泌细胞群。

RELATIONSHIP BETWEEN CATECHOLAMINERGIC OR SEROTONIN- IMMUNOREACTIVE TERMINALS AND OXYTOCINOR VASOPRESSINCONTAINING CELLS OF THE HYPOTHALAMUS IN THE RAT

The monoaminergic afferents to the magnocellular neurosecretory neurons in the hypothalamic supraoptic and paraventricular nuclei (SON and PVN) have been studied in many aspacts. In the present paper, double immunohistochemistry staining method was used to visualize catecholaminergic, i.e. tyrosine hydroxylase-immunoreactive (TH-ir), and serotonin- immunoreactive (5-HT-ir) terminals on oxytocin (OT)- and vasopressin (VP)- containing cells and dendrites not only in the SON and PVN, but also in most of the accessory magnocellular neurosecretory nuclei of the hypothalamus in the rat. Both the 5-HT-ir and TH-ir terminals were found in close proximity to the OT- and VP- containing cells and dendrites in various magnocellular neurosecretory cell groups, but differing in their density. There was fairly high density of the TH-ir endings in most of the accessory neurosecretory cell groups of the hypothalamus. Fairly high to moderate density of the 5-HT-ir terminals were mainly found in the accessory cell groups. It seems that the magnocellular neurosecretory cell groups are differently regulated by CA and 5-HT inputs.