Reduction of feed intake in sheep by enterostatin, the procolipase activation peptide

Enterostatin, a peptide formed during the activation of pancreatic procolipase in the duodenum, is likely a mediator of satiety in the rat. The objective of this research was to determine whether administration of enterostatin into the lateral cerebral ventricle of sheep unfed for 2 h resulted in reduced feed intake. Bolus doses of 2 micrograms did reduce (P < .03) feed intake during the hour after injection by one- to two-thirds of control. Doses 20 micrograms or greater were not effective, and .2 microgram also did not have any statistically significant effect. This range of effective doses was similar to that observed in the rat, and the effective dose of 2 micrograms was approximately 10-fold greater on a per-animal basis, but less on a brain-size basis, than the amount needed to achieve a similar response in the rat. Therefore, enterostatin can reduce feed intake and thus may also be involved in satiety in sheep.