【摘要】 目的:研究牛心内膜内皮细胞（BEEC）腺苷三磷酸双磷酸酶（apyrase）的特性并比较牛心内膜及血管内皮细胞的胞外腺苷酸酶活性。方法:以反相HPLC测定核苷酸含量,以磷离子释放法检测apyrase活性。结果:叠氮钠10mmol·L^-1和氟化钠20mmol·L^-1分别抑制BEEC apyrase 51％及38％活性,而Na⁺/K⁺ -ATP酶抑制剂哇巴因则对BEEC apyrase活性无影响。过氧化氢0.5mmol·L^-1呈时间依赖性地抑制心内膜内皮细胞apyrase活性。BEEC的apyrase活性低于主动脉内皮细胞的apyrase活性,而BEEC的胞外AMP酶则远较血管内皮细胞的活性高。结论:BEEC apyrase具有叠氮钠和氟化钠敏感的、哇巴因不敏感的特性;与血管内皮细胞相比,BEEC apyrase活性较高而胞外AMP酶活性较低。更多还原

【Abstract】 AIM: To characterize the ATP diphosphohydrolase (apyrase) of bovine endocardial endothelial cells, and to compare ecto-adeninenucleotidase activity between bovine endocardial and aortic endothelial cells (BEEC and BAEC). METHODS: The nucleotide was analyzed by reversed phase HPLC and apyrase activity was assayed by inorganic phosphate release. RESULTS: Apyrase inhibitors, both NaN3 10 mmol·L-1 and NaF 20 mmol·L-1, inhibited BEEC apyrase activity by 51 % and 38 %, respectively. The inhibitor for Na+/K+-ATPase, ouabain, did not affect the enzyme activity. Edetic acid 5 mmol·L-1 completely inhibited the enzyme activity. H2O2 0.5 mmol·L-1 downregulated BEEC apyrase activity in a time-dependent manner. The apyrases activities in BAEC were higher than those in BEEC, while the ecto-AMPase activity in BAEC was much weaker than that in BEEC. CONCLUSION: BEEC have NaN3- and NaF-sensitive, ouabain-insensitive apyrase activity. BEEC had high ecto-AMPase activities, and low apyrases activities as compared with BAEC.更多还原