Decrease in voluntary feed intake and pulsatile luteinizing hormone secretion after intracerebroventricular infusion of recombinant bovine leptin in mature male sheep

Abstract

The aim of the present study was to determine whether leptin might play a role in the gonadotrophic response of mature merino rams to changes in the level of nutrition in rams fed ad libitum. Recombinant bovine leptin was infused intracerebroventricularly and voluntary food intake (VFI) and luteinizing hormone (LH) pulse frequency were measured. In Experiment 1, rams (n = 5) were infused for 24 h per day for 5 days with vehicle or with leptin (0.04, 0.4 and 4.0 microg h(-1)). All doses decreased both VFI and LH pulse frequency. In Experiment 2, rams were infused for 24 h per day for 5 days with vehicle (n = 10) or leptin (4 pg h(-1); n = 5); a sub-group of 5 controls was pair-fed to the lept..