长角血蜱唾液腺Apyrase的生物学特性和功能的研究  

APYRASE AND ANTI-PLATELET ACTIVITIES FROM THE SALIVARY GLANDS OF HAEMAPHYSALIS LONGICORNIS

作　　者：程远国[1] 吴厚永[1] 李德昌[2] 李成文[1] 赵彤言[1] 

机构地区：[1]军事医学科学院微生物流行病研究所,北京100071 [2]解放军军需大学动物医学院寄生虫教研室,长春130042

出　　处：《寄生虫与医学昆虫学报》2000年第3期175-182,共8页Acta Parasitologica et Medica Entomologica Sinica

摘　　要：长角血蜱在吸血时 ,其唾液腺中的 apyrase可明显地抑制由 A DP所诱导的血小板聚集反应 ,并呈剂量反应关系 ,1/ 2对唾液腺可以完全抑制血小板的聚集反应。通过 apyrase的动力学、 HPLC分子筛、等电聚焦电泳和温度敏感性实验证明 ,水解 ATP和 ADP并不是 ATP酶、 ADP酶或几种酶共同作用的结果 ,而是一种酶即 apyrase的作用结果。Apyrase对 Ca2 +具有依赖性。而 Mg2 +、Zn2 +、Mn2 +对之影响较小 ,Hg2 +和EDTA是 apyrase的抑制剂。吸血对蜱唾液腺 apyrase活性影响较大 ,吸血 6天时其活性最大 ,吸血后活力明显下降。A pyrase与哺乳动物的 5′-核苷酸酶相似 ,它是一种糖基 -磷脂酰肌醇 ( GPI)膜锚结构蛋白。The salivary gland of Haemaphysalis longicornis secrets an apyrase that inhibitis ADP-depedent platelet aggregation.The aggregation of platelet induced by ADP was inhibited in a dose dependent manner,the full inhibition of platelet aggregation was achieved with half pair of salivary gland homgenate.Kinetic,HPLC chromatography,isoelectric focusing gel electrophoresis and thermal sensitivity assays indicated that the enzymatic activity is the result of a true apyrase and not the result of indpendent or combined different enzyme activities.The apyrase activity was dependent on Ca 2+ and not on Mg 2+ ,Mn 2+ or Zn 2+ ,and was inhibited in the presence of Hg 2+ and EDTA.The pH optimum for both ATPase and ADPase activities was 8 5.Blood feeding has great effect on the apyrae activity,the ATPase and ADPase activities dereased by 45 57% and 48 4% ( P <0 001) respectively 6 days after feeding and 2h later as compared with 6 days after feeding.Apyrase resemble the mammalian nucleotidase in that it is attached to the salivary gland cell membrance by a glycosylphosphatidylinosotol(GPI) anchor.

关 键 词：长角血蜱 唾液腺 APYRASE 血小板聚集 

分 类 号：R384[医药卫生—医学寄生虫学]