[The stress-limiting action of pulsed infrared laser radiation].

Experiments were carried out on male rats to study molecular background of stress-limiting effect of impulse infrared laser radiation (0.89 mu). The motor cortex was subjected to 4.8 W local impulse laser radiation with an impulse length 10(-8) sec, 3000 Hz base frequency and 10 Hz modulating frequency during 10 minutes. The following data were estimated: DNA synthesis in the cells of the cortex, skeletal muscles and thymus recorded by 3H-thymidine inclusion in nuclear DNA, 11-OCS content in blood plasma. It was revealed that IR radiation stimulated DNA synthesis in all the examined tissues of intact animals and animals after proactive physical load (swimming). The preliminary laser radiation was an effective stress-limiting factor for the cortex and thymocytes of swimming rats, but did not prevent decreasing 3H-thymidine inclusion in muscles' nuclear DNA initiated by swimming.