Reproductive toxicology of 1,3-diphenylguanidine: analysis of induced sperm abnormalities in mice and hamsters and reproductive consequences in mice.

The effects of 1,3-diphenylguanidine (DPG) on seminal cytology in hybrid mice and inbred Syrian golden hamsters and on testicular histology and reproductive toxicity in mice were monitored. Treatment consisted of chronic exposure of hamsters and mice to DPG in 0.025% acetic acid ad libitum. Sperm morphology and sperm count, testicular cytology and histology, and reproductive toxicity were monitored 1 wk after exposure. The results show that DPG induces (1) time- and dose-dependent morphologically anomalous sperm in mice and hamsters; (2) significant decreases in sperm count and testicular weight; (3) irregularly shaped seminiferous tubules characterized by the absence of a defined basement membrane, loss of interstitial cells, and limited number of spermatids and spermatozoa in the lumen of the tubules; and (4) reduced fertility indices, implants per pregnancy, and fetal mortality in mice. The coincidence of increased morphologically anomalous sperm and drastic reductions in fertility indices and implants per pregnancy is suggestive of developmental disturbances in the preleptotene and late-spermatogonial cells (5-7 wk after treatment).