大鼠中脑中央灰质内谷氨酸脱羧酶和阿片μ受体共存神经元与脑啡肽、β-内啡肽和强啡肽阳性终末的联系

CONNECTIONS BETWEEN ENKEPHALIN, β-ENDORPHIN AND DYNORPHIN IMMUNOREACTIVE TERMINALS AND GLUTAMATE DECARBOXYLASE/μ OPIOID RECEPTOR CO-EXISTED NEURONS IN THE MIDBRAIN CENTRAL GRAY OF THE RAT

本研究用免疫组织化学三重反应 ,在激光共聚焦扫描显微镜下观察了中脑中央灰质内的谷氨酸脱羧酶和阿片μ受体共存神经元与亮氨酸 -脑啡肽、β-内啡肽和强啡肽阳性终末的联系。结果显示 ,谷氨酸脱羧酶阳性神经元主要散在分布于中央灰质的中、尾段内侧区和腹外侧区 ,多为小型神经元 ;谷氨酸脱羧酶阳性终末在中央灰质全长各区的密度均较高 ;阿片 μ受体阳性的中、小型神经元主要散在分布于中央灰质的中、尾段的腹外侧区 ,在其腹外侧区可见少量谷氨酸脱羧酶和阿片 μ受体共存的小型神经元。在中央灰质全长的内侧区和腹外侧区均能见到较密集的亮氨酸 -脑啡肽、β-内啡肽和强啡肽阳性终末围绕在谷氨酸脱羧酶、阿片μ受体阳性神经元和两者共存神经元的胞体或树突周围并形成密切接触。本研究结果表明 ,中央灰质内含内源性阿片样物质的阳性终末与谷氨酸脱羧酶 /阿片 μ受体共存神经元之间存在密切接触 ,提示内源性阿片样物质对

To observe the connections between leucine enkephalin (L ENK) , β endorphin (β END) or dynorphin (Dyn) immunoreactive terminals and glutamate decarboxylase (GAD)/μ opioid receptor (MOR) co existed neurons within the midbrain central gray (CG) in the rat, immunofluorescence histochemical triple staining technique was used. The staining results were observed with laser scanning confocal microscope. GAD immunoreactive (GAD IR) neurons were mainly encountered in the medial subregion (MS) and ventrolateral subregion (VLS) at the middle and caudal levels of the CG. Most of the sparsely distributed GAD IR neurons were small sized ones. Quite high density of GAD IR terminals was also found within the whole CG. Scattered MOR IR neurons were mainly observed in the VLS at the middle and caudal levels of the CG. A few GAD/MOR co existed neurons were also found in the VLS at the middle and caudal levels of the CG. L ENK , β END and Dyn IR fibers and terminals were quite densely located in all subregions of the CG. Some of them made close contacts with GAD/MOR co existed neurons in the VLS at the middle and caudal levels of the CG. The present results demonstrate that opiate like substances (OLS) containing fibers and terminals made close contacts with GAD/MOR co existed neurons in the CG. These results indicate that OLS might have direct regulatory effects on GABAergic neurons in the CG.