Differences in receptor binding and stability to enzymatic digestion between CCK-8 and CCK-58.


Journal Article

INTRODUCTION AND AIMS: It has been proposed that distinct tertiary structures of the C-terminus of CCK-8 and CCK-58 result in differences in stimulation of pancreatic amylase secretion. Binding of CCK-8 and CCK-58 to CCK-A and CCK-B receptors and stability to enzymatic digestion were used as independent probes for tertiary structure of the C-terminus. METHODOLOGY: Canine CCK-58 was purified from intestinal extracts and CCK-8 was purchased. Their amounts were determined by amino acid analysis. The effect of tertiary structure on receptor binding at CCK-A receptors and CCK-B receptors was evaluated using membrane preparations from mouse pancreas and brain. The influence of C-terminal tertiary structure on stability to enzymatic digestion was evaluated by reacting CCK-8 and CCK-58 with endopeptidase 24:11. RESULTS: CCK-58 was three times more potent than CCK-8 for binding mouse pancreatic membrane CCK-A receptors and equipotent to CCK-8 for binding mouse brain CCK-B receptors. CCK-8 was readily digested by endopeptidase 24:11, whereas CCK-58 was not. CONCLUSIONS: The results strongly support the hypothesis that differences in tertiary structure of the carboxyl terminus of CCK-8 and CCK-58 influence receptor binding and stability to enzymatic digestion.

Full Text

Cited Authors

  • Reeve, JR; McVey, DC; Bunnett, NW; Solomon, TE; Keire, DA; Ho, FJ; Davis, MT; Lee, TD; Shively, JE; Vigna, SR

Published Date

  • October 2002

Published In

Volume / Issue

  • 25 / 3

Start / End Page

  • e50 - e55

PubMed ID

  • 12370550

Pubmed Central ID

  • 12370550

Electronic International Standard Serial Number (EISSN)

  • 1536-4828

Digital Object Identifier (DOI)

  • 10.1097/00006676-200210000-00021


  • eng

Conference Location

  • United States