LYSOPHOSPHATIDIC ACID ACTIVATES NUCLEAR NUCLEOSIDE TRIPHOSPHATASE IN RAT HEPATOCYTES  

作　　者：李菊香 李载权 伍期专 唐朝枢 杜军保 

机构地区：[1]Institute of Cardiovascular Research,Peking University First Hospital,Beijing10003 [2]Department of Physiology and Pathophysiology,Health Science Center,Peking University,Beijing100083 [3]Institute of Cardiovascular Research,Peking University First Hospital,Beijing100034 Department of Physiology and Pathophysiology,Health Science Center,Peking University,Beijing100083

出　　处：《Chinese Medical Sciences Journal》2003年第4期213-217,共5页中国医学科学杂志（英文版）

基　　金：ThisworkwassupportedbytheMajorStateBasicResearchDevelopmentProgramofPeople’sRepublicofChina(G2000056905)andtheNationalNaturalSciencesFoundationofChina(30070308).

摘　　要：Objectives.To observe if lysophosphatidic acid(LPA)can influence nuclear nucleoside triphos-phatase(NTPase)activity of isolated hepatocyte from rat,and to investigate the possible mechanisms by which LPA affects the NTPase.Method.Isolated and cultured hepatocytes from rat liver were exposed to LPA(1×10 -9 ,1×10 -8 and5×10 -8 mol/L)with or without inhibitors of protein kinase C(PKC)and mitogen activating protein kinase kinase(MAPKK),and the NTPase activity on nuclear envelope was assayed using ATP and GTP as substrate,respectively.Results.Nuclear NTPase activity of rat hepatocytes was potently stimulated by incubation of hepato-cytes with LPA in concentration?and time ?dependent manners.In hepatocytes incubated with LPA,nu-clear NTPase activity was significantly higher than that of the control(P<0.01).In hepatocytes preincu-bated with PKC inhibitor H-7or MAPKK inhibitor PD98059,LPA-stimulated activation of nuclear NT-Pase was obviously attenuated.In addition,direct incubation of isolated hepatic nuclei with LPA had no effect on nuclear NTPase activity.Conclusion.LPA is involved in modulating nuclear NTPase activity in hepatocytes.The stimulating effect of LPA on the nuclear NTPase is mediated at least partly by PKC and MAPK-dependent pathway.

关 键 词：lysophoshatidic acid nucleoside triphosphatase HEPATOCYTE 

分 类 号：R341[医药卫生—基础医学]