Immunohistochemistry section of testes and epididymis tissue from tetrodotoxin treated group (A, B) (0.5µg/kg.bw), (C, D) (1µg/kg.bw) of male albino rats (A) numerous immune positive cells for TNFα antibody (arrow) in sertoli cells and spermatogonia. (B) moderate immune positive cells for TNFα antibody (arrow) epididymal epithelial cells lining. (C) mild immune positive cells for TNFα antibody (arrow) mainly in spermatogonia. (D) numerous immune positive cells for TNFα antibody (arrow) in epididymal epithelial cells lining. (DAB- chromogen, X40).