内皮素1和血管紧张素Ⅱ对大鼠肝细胞核核苷三磷酸酶活性的影响  

Effects of endothelin 1 and angiotensin Ⅱ on activites of hepatic nuclear nucleoside triphosphatase in rat

作　　者：李菊香[1] 李载权[2] 庞永正[2] 唐朝枢[1,3] 杜军保[2] 

机构地区：[1]北京大学医学部生理学和病理生理学系 [2]北京大学第一医院心血管研究所 [3]第一医院心血管研究所,北京100034

出　　处：《基础医学与临床》2003年第1期48-52,共5页Basic and Clinical Medicine

基　　金：国家自然科学基金 (30 0 70 30 8)

摘　　要：核被膜核苷三磷酸酶 (nucleosidetriphosphatase ,NTPase)为通过细胞核孔复合体转运mRNA的限速酶。本实验探讨内皮素 1(ET 1)和血管紧张素Ⅱ (AngⅡ )对大鼠肝细胞核NTPase活性的影响。体外分离的大鼠肝细胞核与ET 1或AngⅡ单独或分别与ET 1的ETA受体拮抗剂JKC30 1、ETB受体拮抗剂BQ788或AngⅡ的AT1受体拮抗剂Losartan、AT2 拮抗剂PD12 3177共同孵育肝细胞核 ,分别测定ATP和GTP作底物时 ,肝细胞核NTPase活性。结果发现ATP和GTP作底物时 ,ET 1(10 -11～ 10 -9mol/L)或AngⅡ (10 -11～ 10 -9mol/L)孵育肝细胞核均浓度依赖地增强其NTPase活性 (均P <0 0 1) ,ET 1和AngⅡ对NTPase的刺激作用可分别被JKC30 1(10 -6mol/L)和Losartan (10 -6mol/L)阻断 (P <0 0 1)。ET 1和AngⅡ共同孵育后 ,核NTPase活性与ET 1或AngⅡ单独孵育相比显著增加 (均P<0 0 1)。结果表明 :ETThe putative role of nuclear nucleoside triphosphatase (NTPase) is to provide energy to the nuclear pore complex for poly (A) + mRNA export. The study here was to investigate the influence of endothelin 1 (ET 1) and angiotension Ⅱ (Ang Ⅱ) on the hepatic nuclear NTPase activities. Isolated hepatic nuclei from rat liver were exposed to ET 1 and Ang Ⅱ with or without ET A receptor antagonist JKC301, ET B receptor antagonist BQ788, AT 1 antagonist Losartan and AT 2 antagonist PD123177. NTPase activities were assayed respectively with ATP and GTP as substrates. NTPase activity was increased by the incubation of hepatic nuclei with increasing concentrations of ET 1 (10 -11 ～10 -9 mol/L) or Ang Ⅱ (10 -11 ～10 -9 mol/L) in a concentration dependent manner, regardless of using either ATP or GTP as substrates. Incubation of nuclei with both ET 1 and Ang Ⅱ made a co stimulation to the NTPase activity, as compared with their ET 1 or Ang Ⅱ group alone. Pretreatment with JKC301 (10 -6 mol/L), the increase of NTPase activity induced by ET 1 was greatly inhibited. The increase of NTPase activity induced by Ang Ⅱ was also attenuated by Losartan (10 -6 mol/L). It was found that both nuclear ET 1 and Ang Ⅱ played an important role in the regulation of NTPase activities, which was believed to be mediated by ET A or AT 1 receptors.

关 键 词：内皮素1 血管紧张素Ⅱ 核苷三磷酸酶 肝细胞 

分 类 号：R341[医药卫生—基础医学]