Gavish M
Department of Pharmacology, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa.
J Steroid Biochem Mol Biol. 1995 Jun;53(1-6):57-9. doi: 10.1016/0960-0760(95)00040-7.
Central benzodiazepine (BZ) receptors are located only in the central nervous system and mediate the clinical effects obtained by various BZs. In addition, there is another receptor that binds BZs with different drug specificities, which is located mainly on the outer mitochondrial membrane of various peripheral tissues. Peripheral BZ receptors (PBR) are composed of three subunits: an isoquinoline binding site, a voltage-dependent anion channel, and an adenine nucleotide carrier, with molecular weights of 18, 32, and 30 kDa, respectively. Complementary DNA of the isoquinoline binding subunit has been cloned in rat, calf, and human. The major role of PBR is in the regulation of steroid biosynthesis. Various PBR ligands stimulate the conversion of cholesterol into pregnenolone and the production of steroid hormones. The naturally occurring diazepam-binding inhibitor stimulates in vivo steroidogenesis via binding to PBR. In the female, PBR density is increased in rat and human ovary proportional with greater cell maturation and differentiation. In the male, testosterone modulates PBR density in the genital tract. These results show the strong relationship between PBR and the endocrine system.
中枢苯二氮䓬（BZ）受体仅位于中枢神经系统，介导各种苯二氮䓬类药物产生的临床效应。此外，还存在另一种能以不同药物特异性结合苯二氮䓬类药物的受体，其主要位于各种外周组织的线粒体外膜上。外周苯二氮䓬受体（PBR）由三个亚基组成：一个异喹啉结合位点、一个电压依赖性阴离子通道和一个腺嘌呤核苷酸载体，分子量分别为18、32和30 kDa。异喹啉结合亚基的互补DNA已在大鼠、小牛和人类中克隆出来。PBR的主要作用是调节类固醇生物合成。各种PBR配体刺激胆固醇转化为孕烯醇酮以及类固醇激素的产生。天然存在的地西泮结合抑制剂通过与PBR结合在体内刺激类固醇生成。在雌性大鼠和人类卵巢中，PBR密度随着细胞成熟和分化程度的增加而升高。在雄性中，睾酮调节生殖道中的PBR密度。这些结果表明PBR与内分泌系统之间存在密切关系。
