[Effect of protein kinase C and NO-synthase inhibitors on the radiation-induced cytogenetic adaptive response in cultured Chinese hamster cells].

The effects of the serin-threonin kinase inhibitor--staurosporin and inhibitor of NO-synthase--L-NAME on the radiation-induced adaptive response were studied in fibroblasts of Chinese hamster in culture. We have shown that the adaptive response as measured by the reduction of radiation-induced chromosome aberrations was completely blocked in the presence of staurosporin as well as L-NAME. These inhibitors themselves did not increase the chromosome aberration frequency when cultures were irradiated with 3 Gy alone in the presence of inhibitors. Furthermore, L-NAME noticeably decreased the gamma-rays-induced level of the chromosome aberrations. Our study confirms the participation of protein kinase C in the induction of the adaptive response and first indicates the participation of NO-synthase in this response.