Effects of different doses of ulinastatin on platelets during normothermic cardiopulmonary bypass in rabbits / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effects of different doses of ulinastatin on platelet counts and function after normothermic cardiopulmonary bypass (CPB) in rabbits. Methods Fifty lung-ear white rabbits aged 5-6 months weighing 2.3-3.0 kg were randomly assigned to one of 5 groups (n = 10 each) : control group (group C) and4 ulinastatin groups (group U~1, U_2,U_3,U_4). The rabbits received ulinastatin 1×10~4, 3×10~4, 5×10~4 and 10×10~4 U/kg before CPB in group U~1, U_2, U_3 and U_4 respectively while equal volume of normal saline was given instead of ulinastatin in group C. All rabbits underwent CPB for 30 min at perfusion flow of 72-120 ml·kg~(-1) ·min~(-1). The rectal temperature was maintained at 36.5-37.5℃. Hemodynamic parameters were recorded and blood platelet count, platelet adhesion rate and platelet membrane glycopretein Gp Ⅰ b, Gp Ⅱ b, Gp Ⅲ a receptors were determined before CPB (baseline), at termination of CPB and at 1, 2 and 3 h after CPB. Results The platelet counts were significantly decreased after CPB in all 5 groups (P< 0.05), but there was no significant difference among the 5 groups. The platelet adhesion rates were significantly decreased after CPB as compared with the baseline value before CPB in all 5 groups but the platelet adhesion rates were significantly higher after CPB in group U_4 than in group C. The number of molecules of Gp Ⅰ b, Gp Ⅱ b and Gp Ⅲ a receptors was significantly decreased after CPB in all 5 groups. The number of molecules of Gp Ⅰ b, Gp Ⅱ b and Gp Ⅲ a receptors after CPB was significantly higher in group U_2, U_3 and U_4 than in group C, and there was no significant difference between group U_3 and U_4 . ConclusionUlinastatin 3×10~4-5×10~4 U/kg administered before CPB can inhibit breakdown of platelet membrane glycoprotein receptors. Ulinastatin 10×10~4 U/kg can preserve the platelet adhesion function.