Matsuda Y, Kurihara M, Asami M, Makise J, Kanayama M, Yamanaka M
Central Laboratory, Yokosuka Kyosai Hospital.
Rinsho Byori. 1990 Feb;38(2):177-82.
We examined the localization of glycylproline dipeptidyl aminopeptidase (GPDAP) in the liver tissue and the mechanism of its release into blood flow. An immunohistochemical study using rabbit polyclonal antibody against the purified GPDAP from human liver obtained at autopsy was performed in liver biopsy samples with the peroxidase-antiperoxidase stain technique. GPDAP staining was detected on the liver cell membrane around bile canaliculi. After treatment with deoxycholic acid (DOC) or Triton X-100, this enzyme disappeared. GPDAP was solubilized rapidly from microsome of human liver by treatment with either DOC or Triton X-100. DOC or Triton X-100 solubilized GPDAP coincided with the isozyme that was the specific isozyme in sera of patients with acute hepatitis or obstructive jaundice. These results suggest that GPDAP localizes on the liver cell membrane around bile canaliculi and that this enzyme is released by the detergent action of bile acids.
我们研究了甘氨酰脯氨酸二肽氨基肽酶（GPDAP）在肝组织中的定位及其释放到血流中的机制。使用针对尸检获得的人肝纯化GPDAP的兔多克隆抗体，采用过氧化物酶-抗过氧化物酶染色技术，对肝活检样本进行免疫组织化学研究。在胆小管周围的肝细胞膜上检测到GPDAP染色。用脱氧胆酸（DOC）或 Triton X-100处理后，这种酶消失。通过用DOC或 Triton X-100处理，GPDAP可迅速从人肝微粒体中溶解出来。DOC或 Triton X-100溶解的GPDAP与急性肝炎或梗阻性黄疸患者血清中的特异性同工酶一致。这些结果表明，GPDAP定位于胆小管周围的肝细胞膜上，并且这种酶是通过胆汁酸的去污剂作用释放出来的。
