Heat induced differential pattern of DNA fragmentation in male germ cells of rats.

Spermatogenesis being a highly dynamic processes is highly vulnerable to various stresses including heat stress. Though, the relationship between physiological temperature and male germ cells is certainly immense, the magnitude of spermatozoal damage after exposure to heat is evidently degree and dose dependent. Further, there are contradictory reports related to germ cells apoptosis in relation to temperatures. Thus, currently the dynamics of temperature and time dependence on germ cell apoptosis were studied by modulating the heat treatment strategies. It was observed that the rate of apoptosis increased initially then decreased with time. The DNA fragmentation in the 10,000×g supernatant of testis homogenate of rats that received heat treatment for 15-min, 30-min as well as 45-min treatment with 15-min intermittent period was found to be almost equal. In various heat treated animals, the apoptosis was found to be maximum after day-1 of treatments, which then followed a decreased pattern. These results indicate that there may be an initial induction of apoptosis in the germ cells, which later primed or programmed the other germ cells to activate protective mechanisms against heat induced DNA damage and thus protecting germ cell population to undergo apoptosis at later durations.