Six week old male Swiss albino mice taken from an inbred colony were irradiated with 0.6 and 1.2 Gy of low 60Co gamma rays in the presence (Experimental) and absence (Control) of MPG. Results indicated the infliction of radiation insult and subsequent repair in the testes to be dose dependent, that is higher the dose greater the damage and sluggish the reparative activity. A greater number of surviving germ cells in the experimental tests with fewer dead cells reflected the protective efficiency of the drug against radiation damage to the cell population. Thus MPG not only protects against radiation induced cell death and depletion but also changes the mitotic rate of the stem cells by which an accelerated recovery was brought about.