Specific Binding of Vasoactive Intestinal Peptide Receptor in Cephalic and Caudal Lobes of Anterior Pituitary of Incubating and Laying Hens and Roosters

Abstract

Specific bindings to radioiodinated chicken vasoactive intestinal peptide (VIP) were measured in the membrane fraction of the cephalic and the caudal lobes of anterior pituitary of Japanese native breed of chicken, Gifujidori. The specific binding per mg protein in the cephalic lobe was much greater in incubating hens than in laying hens and less in roosters than in the hens. In the caudal lobe, however, it was not different between the incubating and laying hens and between the hens and the roosters. The greater binding in the cephalic lobe in the incubating hens may be concerned in the incubation behavior through the stimulatory action of VIP for prolactin secretion.