凝血酶、花生四烯酸及阿司匹林对中性粒细胞与血小板之间粘附的影响

目的: 探讨不同浓度的凝血酶、花生四烯酸(AA)和阿司匹林对大鼠血小板与中性粒细胞之间粘附作用的影响。方法: 应用改良的Hamburger等和沈志强等方法观察大鼠血小板与中性粒细胞之间的粘附作用。结果: 凝血酶在50U/L就能促进血小板中性粒细胞之间的粘附,且随浓度增加而增大,在300U/L时达最大作用,再随着浓度的增加,粘附率反而下降。25μmol/L的AA即表现为促进细胞间粘附作用,并随浓度的增加而增强,于100μmol/L时达最大作用,若再增加浓度,则粘附率明显下降;阿司匹林对上述两种血小板激活剂引起的血小板-中性粒细胞间的粘附具有明显抑制作用,且呈浓度相关性,其IC₅₀分别为62.9和51.4μmol/L。结论: 凝血酶和AA在一定范围内呈浓度依赖性促进血小板-中性粒细胞的粘附作用,但浓度再增加,则粘附率反而下降;阿司匹林可明显抑制凝血酶和AA引起的血小板-中性粒细胞粘附作用。

Effects of thrombin, arachidonic acid and aspirin on leukocyte-platelet adhesion

AIM: To investigate the effects of different concentrations of thrombin, arachidonic acid (AA) and aspirin on leukocyte-platelet adhesion. METHODS: The methods of Hamburger et al and Shen Zhi-qiang et al were used to study the adhesion between platelets and leukocytes in rats. RESULTS: 50 U/L of thrombin markedly stimulated the binding between platelets and leukocytes; the efficacy of thrombin increased with its concentration and produced the maximum effect at 300 U/L. But the adhesion rate decreased while the concentration of thrombin was more than 300 U/L. 25 μmol/L of AA significantly enhanced the binding of platelets to leukocytes; the efficacy of AA increased with its concentration and obtained the maximum effect at 100 μmol/L. The adhesion rate, however, decreased while the concentration of AA was more than 100 μmol/L. Aspirin could inhibit thrombin-or AA-induced adhesion between platelets and leukocytes. CONCLUSION: It is suggested that thrombin and AA, in a certain range of concentrations, concentration-dependently induced the binding of platelets to leukocytes; the adhesive rate, however, decreased as the concentration of the above inducers increased. Aspirin could inhibit platelet-leukocyte adhesion stimulated by thrombin and AA.