Xiang Zhenghua, He Cheng, Burnstock Geoffrey
Department of Biochemistry and Neurobiolgy, Second Military Medical University, Shanghai, PR China.
Brain Res. 2006 Jul 12;1099(1):56-63. doi: 10.1016/j.brainres.2006.04.126. Epub 2006 Jun 12.
In this study, the P2X(5) receptor was found to be distributed widely in the rat hypothalamus using single and double labeling immunofluorescence and reverse transcriptase-polymerase chain reaction (RT-PCR) methods. The regions of the hypothalamus with the highest expression of P2X(5) receptors in neurons are the paraventricular and supraoptic nuclei. The intensity of P2X(5) immunofluorescence in neurons of the ventromedial nucleus was low. 70-90% of the neurons in the paraventricular nucleus and 46-58% of neurons in the supraoptic and accessory neurosecretory nuclei show colocalization of P2X(5) receptors and arginine vasopressin (AVP). None of the neurons expressing P2X(5) receptors shows colocalization with AVP in the suprachiasmatic and ventromedial nuclei. 87-90% of the neurons in the lateral and ventral paraventricular nucleus and 42-56% of the neurons in the accessory neurosecretory, supraoptic and ventromedial nuclei show colocalization of P2X(5) receptors with neuronal nitric oxide synthase (nNOS). None of the neurons expressing P2X(5) receptors in the suprachiasmatic nucleus shows colocalization with nNOS. These findings provide a morphological basis for possible functional interactions between the purinergic and nitrergic or vasopressinergic neurotransmitter systems.
在本研究中，采用单标和双标免疫荧光以及逆转录聚合酶链反应（RT-PCR）方法发现P2X(5)受体广泛分布于大鼠下丘脑。下丘脑神经元中P2X(5)受体表达最高的区域是室旁核和视上核。腹内侧核神经元中P2X(5)免疫荧光强度较低。室旁核中70 - 90%的神经元以及视上核和副神经分泌核中46 - 58%的神经元显示P2X(5)受体与精氨酸加压素（AVP）共定位。在视交叉上核和腹内侧核中，表达P2X(5)受体的神经元均未显示与AVP共定位。外侧和腹侧室旁核中87 - 90%的神经元以及副神经分泌核、视上核和腹内侧核中42 - 56%的神经元显示P2X(5)受体与神经元型一氧化氮合酶（nNOS）共定位。视交叉上核中表达P2X(5)受体的神经元均未显示与nNOS共定位。这些发现为嘌呤能与一氧化氮能或加压素能神经递质系统之间可能的功能相互作用提供了形态学基础。
