LEPTIN INJECTED INTO THE 4TH VENTRICLE INHIBITS GASTRIC-EMPTYING

THE effect of leptin on gastric emptying of glucose was studied in fre ely moving rats bearing intragastric fistulas. Leptin (0.39 mu g and 3 .9 mu g) injected into the fourth ventricle inhibited gastric emptying significantly, whereas s.c. administration of leptin (10 mu g/kg) had no effect. Leptin receptor immunoreactivity, revealed by an antiserum that recognizes all leptin receptor isoforms, was demonstrated in cho line acetyltransferase (ChAT)-containing neurones of the dorsal motor nucleus of the vagus nerve (DMX). The data indicate that leptin acts c entrally to suppress gastric emptying possibly via leptin receptors lo cated on cholinergic DMX neurones.