Effects of dinoseb, 4,6-dinitro-o-cresol, and 2,4-dinitrophenol on rat Sertoli-germ cell co-cultures.

The effects of dinoseb (DNBP), a known testicular toxicant in the rat, on germ cells were investigated in Sertoli-germ cell co-cultures. Two DNBP-related dinitrophenolic compounds, 4,6-dinitro-o-cresol (DNOC) and 2,4-dinitrophenol (DNP), were also examined, as testicular toxicity of these compounds had not been elucidated. Cultures were exposed to each compound (10(-7)-10(-4)M) for 24h and examined for the number and viability of detached cells and morphologic alterations under a light microscope. DNBP significantly increased the number of detached cells (10(-5) and 10(-4)M) and suppressed their viability (10(-6)-10(-4)M). Morphologic observations revealed degenerative alterations in the germ cells and Sertoli cells. Similar effects as observed after DNBP exposure were evident at 10(-4)M DNOC and 10(-4)M DNP. These results demonstrate that DNBP, DNOC, and DNP have in vitro toxicity to these cell populations at high concentration, and suggest the possibility that DNOC and DNP also cause testicular damage in experimental animals and humans.