AJP - Gastrointestinal and Liver Physiology, Vol 246, Issue 3 296-G304, Copyright © 1984 by American Physiological Society
Radioreceptor and biological characterization of cholecystokinin and gastrin in the chicken
S. R. Vigna
Radioimmunoassay, radioreceptor assays, and bioassays were used to
demonstrate that chicken brain and antrum extracts contain cholecystokinin
(CCK)-like and gastrinlike peptides, respectively. C-terminal-specific
radioimmunoassay of partially purified chicken CCK and gastrin gave
dilution curves parallel to those of the mammalian peptides. Mouse cerebral
cortical and rat pancreatic membrane radioreceptor assays were used to
differentiate CCK- from gastrinlike peptides on the basis of the different
CCK versus gastrin specificities of the two receptors. Confirmation of the
biological activity of chicken brain CCK was obtained by stimulation of
amylase secretion from rat pancreatic lobules in vitro. The specificity of
this response was demonstrated by the inhibition of chicken CCK-stimulated
amylase secretion by the specific CCK receptor antagonist dibutyryl cGMP.
Chicken antral gastrin stimulated gastric acid secretion from the rat
stomach in vivo. In contrast to previous hypotheses, it is proposed that
chickens have significant amounts of an antral gastrinlike peptide and that
therefore it is possible that gastrin is involved in the physiological
regulation of gastric acid secretion in chickens.
