IGF1 and Testicular atrophy: However, in the group of rats with testicular atrophy treated for four weeks with low doses of IGF-I, a partial recovery was observed with an increase of the levels of both free (p < 0.05 vs untreated group) and total testosterone (p = 0.06 vs untreated group) and a significant reduction of the estradiol/total testosterone ratio (Table 4).