Effects of fluoroacetate on the testis of the rat.

Rats recieving 20, 6.6 or 2.2 p.p.m. sodium fluoroacetate in the drinking water were killed daily during the 7 days of treatment and at more widely spaced intervals in the succeeding 21 days. Testicular weight and ATP concentrations decreased in rats receiving 20 or 6 p.p.m. fluoroacetate, while citrate concentrations were elevated and morphological damage was seen in the testes of all the treated rats. Initial cellular changes common to the three treatment groups included altered appearance and decreased numbers of spermatids, and formation of spermatid and spermatocyte giant cells. At the two higher concentrations damage progressed to marked seminiferous tubule atrophy. Regeneration of the seminiferous tubules was complete by 7 days after treatment, in the rats given 2 p.p.m. but regeneration was not complete by Day 21 after treatment in those receiving the higher doses. Spermatogenesis was abnormal in some instances during the regneration period in these groups. The findings are consistent with impaired energy production via blockage of the Krebs cycle, and subsequent impairment of carbohydrate metabolism through the Embden-Meyerhof pathway.