小鼠正常肝、再生肝和腹水型肝癌H22a细胞酪氨酸蛋白磷酸酶的比较研究

小鼠肝在再生过程中,胞浆酪氨酸蛋白磷酸酶(PTPP)活力比正常肝有明显升高,并且伴有时相变化,,手术后24—48h活力达到最高,而H22a细胞各组分的活力都比正常肝低。PTPP在正常肝细胞的溶酶体中分布最高;再生肝中则在细胞核、胞浆和微粒体中更集中;在H22a细胞中,PTPP的活力分布趋于平均化。再生肝和H22a细胞胞浆中都缺少正常肝的a、b两个PTPP活力峰,其它五个主要PTPP峰与正常肝无根本的差别。

Comparative Study of Protein Phosphatases of Mice Normal Liver, Regenerating Liver, and Mice H22a Hepatoma Ascites Cell

In regenerating liver of mice,marked increase of PTPP activity in cytosol was observed.The PTPP activity varied with time and reached the highest level between 24 to 48 hours after hepatectomy.In H22a cells the PTPP activity found in every subcellular fraction was lower than that of the normal liver.The PTPP activity was mostly concentrated in lysosomes of normal liver,but mainly distributed in nucleus,cytosol and microsomes of regenerating liver.In H22& cells PTPP activity seemed distribute evenly.Five similar major PTPP peaks (I-V) were obtained on DEAE cellulose chromatography of cytosols from all three types of liver cells studied.However,two additional PTPP peaks,a and b,were also obtained from cytosol of liver.