Induction of antral gastrin cell proliferation by refeeding of rats after fasting.

The proliferation of antral gastrin cells after fasting and refeeding of rats was studied by using a quantitative histologic method for determining the gastrin cell number and a radioautographic technique after injections of tritiated thymidine for recognizing and quantitating the newly formed gastrin cells. The total number of gastrin cells decreased 68% (P less than 0.01) after a 4-day fasting period, whereas refeeding of rats during 6 days after a 4-day fasting period resulted in a 79% (P less than 0.01) increase of the gastrin cell mass. The labeling index of gastrin cells after six daily injections of tritiated thymidine given during this period of refeeding was significantly (P less than 0.01) increased when compared with this value in control animals. The observed intensity of the proliferative response during refeeding was compatible with the increase in gastrin cell number observed during refeeding. These observations indicate that a new population of gastrin cells is formed in the antral glands when rats are refed after fasting.