Agrawal Y P, Peura T, Vanha-Perttula T
Department of Anatomy, University of Kuopio, Finland.
J Reprod Fertil. 1989 May;86(1):185-93. doi: 10.1530/jrf.0.0860185.
gamma-Glutamyl transpeptidase (gamma-GT), its substrate (GSH) and hydrolytic product (L-glutamic acid) were measured biochemically in mouse reproductive tissues. The epididymal caput and seminal vesicles showed the highest specific activities of gamma-GT, while GSH and L-glutamic acid were widely distributed in all tissues. Histochemically, gamma-GT displayed a strong apical and supranuclear reaction and a moderate basal activity in the ductuli efferents, a weak luminal reaction in the first, a moderate apical reaction in the second and a strong apical and supranuclear reaction in the third segment of the epididymal caput. In the epididymal corpus and cauda, the gamma-GT reaction was confined to the tubular lumina but an apical reaction was also present in the cauda. The daily administration of acivicin (12 mg/kg body weight), an irreversible inhibitor of gamma-GT, for 14 days resulted in a 60% suppression of the enzyme activity in the epididymal caput, while the gamma-GT inhibition in the kidney was greater than 95%. The treatment caused no change in the activity of alanyl aminopeptidase. Histochemically, the basal and supranuclear gamma-GT activities in the ductuli efferents and the third epididymal segment were suppressed, but the apical reactions were maintained. The in-vivo suppression of epididymal gamma-GT activity may have implications in the control of post-testicular sperm maturation.
在小鼠生殖组织中对γ-谷氨酰转肽酶（γ-GT）、其底物（谷胱甘肽，GSH）和水解产物（L-谷氨酸）进行了生化测定。附睾头和精囊显示出最高的γ-GT比活性，而GSH和L-谷氨酸广泛分布于所有组织中。组织化学研究表明，γ-GT在输出小管中显示出强烈的顶端和核上反应以及中等强度的基底活性，在附睾头第一段管腔反应较弱，第二段顶端反应中等，第三段顶端和核上反应强烈。在附睾体和附睾尾，γ-GT反应局限于管腔，但附睾尾也存在顶端反应。每天给予γ-GT不可逆抑制剂阿西维辛（12毫克/千克体重），持续14天，导致附睾头酶活性抑制60%，而肾脏中γ-GT抑制率大于95%。该处理对丙氨酰氨基肽酶活性无影响。组织化学研究显示，输出小管和附睾第三段的基底和核上γ-GT活性受到抑制，但顶端反应得以维持。附睾γ-GT活性的体内抑制可能对睾丸后精子成熟的控制有影响。
