Effects of stressful conditions on the development and movement of reproductive cells in Schistosoma mansoni.

Adult S. mansoni exposed to 3H-thymidine to label reproductive cells were cultured in vitro, maintained intraperitoneally, and transplanted to the hepatic portal vein of hamsters in unisexual infections. Daily samples were taken, processed for autoradiography, and observed for abnormal morphological and development characteristics. Males cultured in vitro did not produce labeled sperm and the testes exhibitied necrotic changes by the 5th day. Vitelline cell formation was normal for the first 5 days, but after that time both vitellaria and ovary showed degenerative changes. Males and females were still alive after 18 days of culture. Worms transferred to the peritoneal cavity were dead after 3 days, and no signs of reproductive development occurred during that time. Most males and a few females were encapsulated by cells thought to be of host origin. Males transplanted into hamsters in unisexual infections produced sperm in the normal time period and showed no morphological deterioration after 8 days. Females similarly handled were degenerating by day 3 and dead by day 6. Development and movement of reproductive cells was not detected in these females.