| Abstract: | After mating with a sexually active male, groupsof female Sprague-Dawley rats were injected withcysteamine (400 mg/kg, subcutaneously) at day 0(controls), day 5 (early-stage pregnancy), and day 18(late-stage pregnancy) of pregnancy. In contrast tolate-stage pregnancy rats, early-stage pregnancy animalsshowed a decrease of cysteamine-induced gastroduodenallesions. When subjected to cysteamine injection, both nonpregnant female and male rats treated foreight days with progesterone (300  g/rat,subcutaneously) showed a reduced incidence ofgastroduodenal lesions. No effect was found in animalspretreated with 17 -estradiol (200 g/rat,subcutaneously). Furthermore, increased gastroduodenalmucus levels were found in early-stage pregnancy ratsand in animals pretreated with progesterone. Theseresults suggest that increased progesterone plasma levelsduring early-stage pregnancymay be involved inpregnancy-induced gastric and duodenal protection. Thiseffect may be related to an increase in gastric andduodenal mucus production induced by thishormone. |
