Abstract
As an artificial material comes in contact with blood during extracorporeal circulation, it will rapidly adsorb protein onto its surface. This adsorbed protein layer will determine all further events, namely, the activation of contact phase, coagulation systems, platelets, leukocy-tes, and complements. In a previous report we discussed Poly2methoxyethylacrylate (PMEA). PMEA suppresses the adsorption and denaturation of plasma protein. In the present study, a PMEA-coated oxyge-nator (Group P) was compared to a heparin-coated oxy-genator (Group H) and a non-coated oxygenator (Group N) under conditions of in vitro circulation using human blood. The results of this study indicated that in comparison to Group N, Group P allowed retention of a significantly larger percentage of white blood cells and platelets in blood and production of a significantly smaller amount of Bradykinin, TAT, β-TG, and PMN-elastase. There were no significant differences between Group P and Group H. After 6 h, circulation adsorbed protein on the oxygenator was extracted and analyzed by immunoblotting. It was considered that the adsorbed amount of fibrinogen on the Group P membranes was smaller than that of Group N. Group P showed biocompatibility equal to that of Group H. It was co-nsidered that the biocompatibility of Group P was mainly due to lower level of protein adsorpton, as well as being a result of the lower degree of denaturation.