Effect of cardiopulmonary bypass for 30 min on structure and mechanical properties of erythrocyte membrane surface / 中国病理生理杂志

ABSTRACT

AIM:To observe and analyze the effect of cardiopulmonary bypass ( CPB) for 30 min on surface ultra-structure and mechanical properties of the erythrocyte membrane by atomic force microscopy (AFM).METHODS:Ten cases of elective patients in cardiac surgery were selected in the study and divided into control ( CON) group and CPB group.The central venous blood (2 mL) before surgery and 30 min after CPB was collected with heparin anticoagulation . The non-circular red blood cells were counted under a stand fluorescence microscope .AFM was used to examine the ultra-structure of the membrane surface and measure the force curve of the erythrocytes .RESULTS:The percentage of non-cir-cular red blood cells in CPB group showed no statistically significant differences as compared with CON group .AFM images showed that the significant differences of membrane surface concave and convex , evenness , particle distribution , the sur-face average roughness (Ra), the surface root mean square roughness (Rq) and cell membrane adhesion between CPB group and CON group were observed .However, the membrane deformation resilience and curve slope had no significant difference between the 2 groups.CONCLUSION:Cardiopulmonary bypass for 30 min changes the morphology and ultra-structure of the erythrocyte membrane surface , and increases the adhesion between cells .