Species differences in platelet function

通过人、猴、狗、兔和大鼠洗净血小板孵育，引入钙离子敏感光蛋白aequorin。细胞内钙离子浓度对凝血酶诱导的血小板活化的调节作用在不同动物中值不同，但外排的阶段几乎相同。在加入吲哚美辛后，胶原诱导的人、猴和大鼠血小板的两相钙离子外排变成了一个相。这些结果表明，在不同的刺激下，动物细胞内钙离子外排的值和阶段是不同的。采用商业RIA试剂盒测定人、恒河猴和食蟹猴血小板ATP含量。结果表明，人类>与恒河猴>有密切关系。人血小板因子4 （PF4）浓度是家兔的5.2倍，是其他动物的8.1 ~ 8.2倍。这些发现表明血小板储存池存在差异。sds -聚丙烯酰胺凝胶电泳结果显示，人和猴细胞膜的蛋白质和糖蛋白结构相似，但与其他动物有明显差异。玻璃珠在大鼠体内的血小板滞留率高于人，随着年龄的增长而降低。为了测定大鼠血小板环氧合酶和脂氧合酶的活性，必须增加花生四烯酸的浓度作为底物。这种酶在大鼠体内的活性比在人体内低得多。电镜观察显示，ADP刺激兔和狗血小板中ATP释放模式的差异提示血小板致密颗粒的数量和定位存在差异。这些发现表明有必要进一步研究血小板功能的物种差异。

The calcium ion sensitive photo-protein aequorin was introduced by incubation into washed platelets of human, monkey, dog, rabbit, and rat. The intracellular calcium ion concentration in mediating thrombin-induced platelet activation differed in value among animals but the phases of efflux were almost the same. Two phases of Ca ion efflux in collagen-induced activation of human, monkey, and rat platelets became one phase upon addition of indomethacin. These findings indicated differences in the values and the phase of intracellular calcium ion efflux with each stimulation in animals.Human, rhesus and cynomolgus monkey blood platelet ATP contents were determined using a commercial RIA kit. The results showed the relation human > rhesus > cynomolgys. The concentration of human platelet factor 4 (PF4) showed a value 5.2-fold that of rabbit, and a value 8.1-8.2-fold that of other animals. These findings indicated differences in the storage pool in the platelets.The proteins and glycoproteins of the human and monkey membranes as determined SDS-polyacrylamide gel electrophoresis showed mutually similar patterns, but were clearly different from those of the other animals.Platelet retention by glass beads was higher in rat than human and decreased with aging in contrast with the case in human.In order to measure the cyclo-oxygenase and lipoxygenase activites in rat platelets, it was necessary to increase the arachidonic acid concentration as substrate. The enzyme activites in the rat were found to be much lower than in human.Difference in the ATP release pattern in ADP stimulated platelets of rabbit and dog suggested the existance of differences in the number and localization of platelet dense granules according to electron microscopic observations.These findings show the necessity of further investigation of species differences in platelet functions.