EFFECTS OF SUB-TOTAL GASTRO-INTESTINAL PANCREATECTOMY OF THE RAT FOETUS

Abstract

SUMMARY: Sub-total pancreatectomy in utero was performed in 18-day-old rat foetuses. Pancreatectomized, sham-operated and control foetuses were collected 3 days later and body weight, glucose and insulin levels in blood, and glycogen content and glucose-6-phosphatase (G-6-Pase) activity of the liver were determined. Pancreatectomized foetuses showed only very small pancreatic remnants (≤ 1 mg) and accordingly their insulin levels were much lower (four to five times) than those of sham-operated or control foetuses; their blood glucose levels were slightly increased and liver glycogen content and G-6-Pase activity were slightly reduced; their body weights were also reduced. These results are discussed in relation to other relevant data in the literature. They afford direct experimental evidence of the endogenous origin of insulin in the foetal blood. It is suggested that during the last days of intra-uterine life insulin merely completes the action of the glucocorticoids on glycogen storage in rat foetal liver and probably contributes to foetal body growth. Its relative ineffectiveness on the foetal blood glucose level is not explained. As pancreatectomized foetuses develop sub-normal liver G-6-Pase activity, glucagon is probably not responsible for the increase in this activity occurring during normal development before birth.