Effect of gonadectomy on epidermal growth factor values in the gastrointestinal tract of male and female CD-1 mice.

The effects of gonadectomy on the epidermal growth factor (EGF) concentrations in the gastrointestinal tract of CD-1 mice were studied. The EGF concentrations in the gastrointestinal tissues were always higher in males than in females. Gonadectomy led to a decrease in the EGF concentration in males, and an increase in females. Gonadectomy with sialoadenectomy led to a decrease in the EGF concentrations in the gastrointestinal tract of both sexes; the most significant effect being observed in the stomach. Orchidectomy led to a decrease in total body weight, and to a significant decrease in the weight and the protein concentration (ng.g-1 wet weight of tissue) of the submandibular gland, but had no significant effect on the other tissues of the gastrointestinal tract of male mice. Body, tissue weights, and protein concentrations did not change with oophorectomy. This study shows that male and female gonads have a profound effect on the EGF content of the tissues of the gastrointestinal tract and suggests that the submandibular gland also influences the EGF concentration in gastrointestinal tissues in mice.