Basnakian A G, Boubnov N V, Kirsanova I D, Votrin I I
Institute of Biological and Medical Chemistry, USSR Academy of Medical Sciences, Moscow.
Biochem Int. 1991 Jun;24(3):429-37.
DNase activity in the presence of Ca2+ + Mg2+, Mg2+ alone, Mn2+ alone, or EDTA, and topoisomerase I activity were measured in nuclear extracts of diethylnitrosamine (DEN)-induced hepatomas, regenerating, fetal, and normal rat livers. In hepatoma tissue, the Ca/Mg-dependent DNase activity was lower than in normal tissue and nearly the same as in fetal liver. In the poorly differentiated hepatomas, Mn-dependent DNase activity was higher than in both moderately and well differentiated ones and than in normal liver tissue. The activity of topoisomerase I in hepatomas and in regenerating liver was lower than in normal liver tissue.
在存在Ca2+ + Mg2+、单独的Mg2+、单独的Mn2+或乙二胺四乙酸（EDTA）的情况下，对二乙基亚硝胺（DEN）诱导的肝癌、再生肝、胎肝和正常大鼠肝脏的核提取物中的脱氧核糖核酸酶（DNase）活性以及拓扑异构酶I活性进行了测定。在肝癌组织中，钙/镁依赖性DNase活性低于正常组织，与胎肝中的活性几乎相同。在低分化肝癌中，锰依赖性DNase活性高于中分化和高分化肝癌以及正常肝组织。肝癌和再生肝中拓扑异构酶I的活性低于正常肝组织。
