Role of gastrin in mucosal DNA synthesis after vagotomy and atropine in the rat.

The purpose of this study was to examine 1) the influence of the cholinergic innervation of the stomach on the rate of DNA synthesis in the fundic mucosa of the rat and 2) the possibility that hypergastrinemia might be involved in the response. Repeated injections of atropine in fasting rats increased by 40% the rate of DNA synthesis in the oxyntic gland mucosa. Two weeks after truncal vagotomy, the DNA synthesis rate in oxyntic gland mucosa was increased 64% compared to sham-operated control animals. In the rat colon, atropine administration produced a 56% increase in DNA synthesis compared to saline-injected controls. The injection of pentagastrin in fasting rats also increased the DNA synthesis rate in both stomach and colon, but pentagastrin combined with either atropine or vagotomy stimulated DNA synthesis no more than pentagastrin alone. Cholinergic interruption by atropine or vagotomy elevated endogenous serum gastrin concentrations, indicating that the observed DNA stimulation may be mediated by hypergastrinemia.