Structural evaluation of the peritubular sheath of rat's testes after administration of ribavirin: A possible impact on the testicular function

Effects of ribavirin on the structure of peritubular sheath (PS) of seminiferous tubules and on testicular functions were studied. We found that ribavirin at a dose of 4mg/kg/day for 4weeks produced a significant reduction in testosterone level (6.3 +/- 0.2; P < 0.001) and in spermatogenic score count (3.8 +/- 0.2; P < 0.001) compared to control values. The thickness of PS (17.8 +/- 1.13) and tubular lumen perimeter (1024.7 +/- 67) was significantly increased compared to controls (10.7 +/- 0.70; P < 0.001 and 808 +/- 25; P = 0.004, respectively). The length of germinal epithelium (411.8 +/- 39) and tubular external diameters (1661.8 +/- 115) was significantly reduced compared to control values (708.4 +/- 40; P < 0.001 and 2358.8 +/- 169; P < 0.001, respectively). The basement membranes (BMs) were thickened with great deposition of collagen. Myoid cells showed altered structure and extracellular matrix revealed disorganization by excessive collagen I and IV accumulation. Testicular damage was established histologically. Evidence of apoptosis was detected in germ cells. There was a significant increase in integrated density of Casp-3 expression (38,121,743 +/- 1,763,420; P < 0.001) in seminiferous tubules compared to control (24,788,409 +/- 1,900,140). It is concluded that ribavirin can cause alterations of the testicular function and structure with increased apoptosis in the tissues after 4weeks of administration. The damaging effect could be persuaded by destruction of the peritubular sheath.