(a) C group. The basal membrane of the seminiferous tubule (right red arrow) has normal thickness (PAS ×100). (b) S group. In interstitial area connective tissue is increased (red bordeed star); diameter of the seminiferous tubule is reduced and basement membrane of seminiferous tubule (right red arrow) has become thicker than that of S group (PAS ×100). (c) LRS group. Basement membrane thickness (right green arrow) and diameter of seminiferous tubules are similar in the C group (PAS ×100). (d) HRS group. Basement membrane thickness (right green arrow) and diameter of seminiferous tubules are similar in the C group (PAS ×100).