The effect of dibromochloropropane (DBCP) on in vitro cyclic AMP levels and testosterone production in rat testes.

Adult male rats were injected s.c. once a week for 3 weeks with DBCP, 20 mg/kg BW. Animals were sacrified 20 weeks after last injection. Body and testes weights were recorded and testes were taken for standard histological preparation and for in vitro experiments. The in vitro experiments were carried out on testes slices (90-110 mg) incubated for 3 h with or without the addition of hCG to the incubation medium. Cyclic AMP content of the tissue as well as testosterone released into the incubation medium were determined. Testes weights of DBCP treated animals were 68% lower than that of controls. All semiferous tubules were damaged and shrunken, thus, their number per microscope field was 2.6 times that of controls. Cyclic AMP levels in testes slices were similar in both DBCP treated and controls. The addition of hCG stimulated cyclic AMP accumulation to a much higher level in the DBCP treated than in controls. When calculated per one pair of testes the content in unstimulated pair was more than twice that of DBCP treated. Stimulation of hCG increased both DBCP treated and controls to similar levels. Testosterone release into the medium by slices was higher in DBCP treated than in controls and so was also the increment due to hCG stimulation. Similar results were obtained when testosterone release was calculated per one pair of testes. It is suggested that since the major testicular compartment damaged by DBCP is the tubular one, the proportion of the interstitium per testicular unit weight is larger than in controls, thus, cyclic AMP content increment due to hCG stimulation is much higher.(ABSTRACT TRUNCATED AT 250 WORDS)