Beart P M, Sheehan K A, Manallack D T
University of Melbourne, Clinical Pharmacology and Therapeutics Unit, Austin Hospital, Heidelberg, Victoria, Australia.
J Cereb Blood Flow Metab. 1988 Dec;8(6):879-82. doi: 10.1038/jcbfm.1988.146.
Radioreceptor methods were used to quantitate the N-methyl-D-aspartate (NMDA) receptor-complex of ovine cerebral microvessels and cerebral gray matter. Specific binding of D[3H]2-amino-5-phosphono-pentanoate and [3H]1-[1-(2-thienyl)cyclohexyl]piperidine, ligands for the NMDA primary acceptor site and ionophore, respectively, was found in cerebral gray matter but was not detectable in membranes prepared from brain microvessels enriched in capillaries. Sigma receptors, another locus of action for phencyclidine congeners, were also not present on microvessels but were found in cortical homogenates. On the other hand, cerebral microvessels and gray matter contained significant numbers of beta-adrenoceptors. Our results indicate the NMDA receptors and NMDA antagonists are unlikely to regulate the function of the cerebral microvasculature.
采用放射受体法对绵羊脑微血管和脑灰质中的N-甲基-D-天冬氨酸（NMDA）受体复合物进行定量分析。分别作为NMDA主要受体位点和离子载体配体的D-[3H]2-氨基-5-膦酰基戊酸和[3H]1-[1-(2-噻吩基)环己基]哌啶的特异性结合在脑灰质中被发现，但在富含毛细血管的脑微血管制备的膜中未检测到。西格玛受体是苯环己哌啶同系物的另一个作用位点，在微血管中也不存在，但在皮质匀浆中被发现。另一方面，脑微血管和灰质含有大量的β-肾上腺素能受体。我们的结果表明，NMDA受体和NMDA拮抗剂不太可能调节脑微血管的功能。
