PCNA and Testicular atrophy: Testicular cellular proliferation, as evaluated by PCNA positive cells, was significantly reduced in both groups with testicular atrophy: IGF-I therapy induced an improvement but it did not reach statistical significance (mean of PCNA + cells scored in 30 tubuli for each animal; CO: 63.8 ± 1; AT: 36 ± 8, p < 0.001 AT vs CO; AT+IGF: 47 ± 5, p < 0.05 CO vs AT+IGF).