AJP - Gastrointestinal and Liver Physiology, Vol 250, Issue 5 594-G597, Copyright © 1986 by American Physiological Society
Maturation of cholecystokinin receptors in pancreatic acini of rats
Y. K. Leung, P. C. Lee and E. Lebenthal
Amylase secretion by fetal and newborn rat pancreata was shown not to
respond to cholecystokinin (CCK) stimulation. Binding of 125I-Bolton-Hunter
(125I-BH)-CCK-8 to dispersed pancreatic acini from rats at various
perinatal ages was measured and compared with adults. Binding occurred
maximally at 30 min at 37 degrees C at all ages. Maximal binding increased
with age. The capacity and affinity of the CCK-receptor binding system was
analyzed by Scatchard's method. The results revealed that the capacity of
the high-affinity component gradually increases with age, whereas that of
the low-affinity component remains relatively constant. Amylase secretion
due to CCK stimulation also increases with age, suggesting that the lack of
responsiveness of pancreata of pups to secretagogue is due to a low binding
capacity of the high-affinity component of the receptors.
