Effect of microwaves, high energy electrons and gamma irradiation on the osmotic resistance of human erythrocyte membranes

The effects of 5 MeV electrons and of gamma irradiation at 0 degrees C as w ell as the effects of 2.45 GHz microwaves at -196 degrees C on the osmotic resistance of human erythrocyte membranes are presented. Both electron and gamma radiation in the range 0-400 Gy induced no haemolysis, indicating tha t the membrane modifications due to radiation interaction do not reach a cr itical point to cause swelling of the cells and consequent lysis. The micro wave irradiated erythrocytes showed a haemolysis degree between 6-16% in th e irradiation time range of 0-5 min. The osmotic stress experiments perform ed after irradiation showed that the gamma irradiated erythrocytes exhibite d an almost similar behaviour at all irradiation doses whereas the electron irradiated samples showed a much larger increase in the haemolysis degree, and in the case of a certain electron dose (100 Gy), the haemolysis was fo und much smaller than for the control sample. ii similar behaviour of the e rythrocytes was found in the case of microwave irradiation of the cryoprote cted erythrocytes at -196 degrees C: the sample irradiated for 6 min develo ped a haemolysis degree much smaller than for the control (70% from the non irradiated sample haemolysis). Our experimental data suggest that electron radiation and gamma radiation have different impacts on the erythrocyte hae molysis in the dose range used. Much more experimental data is necessary in order to clarify the similarity between the results obtained in the case o f electron irradiation at 0 degrees C and microwave irradiation at -196 deg rees C, in the two different sets of irradiation conditions (liquid samples at 0 degrees C and frozen samples at -196 degrees C).