Résumé
We report on the synthesis of some analogs of the C-terminal heptapeptide of cholecystokinin in which the C-terminal primary amide has been deleted and the L-tryptophan replaced by a D-tryptophan. These analogs were evaluated
in vitro for their ability (i) to recognize the CCK receptor on rat pancreatic acini and on guinea pig brain membranes; (ii) to stimulate amylase release from rat pancreatic acini. Although previous works suggested that the C-terminal primary amide is essential for exhibiting a full biological response on pancreatic acini, this study does not confirm this hypothesis.
The synthesis of some analogs of the C-terminal heptapeptide of cholecystokinin in which the C-terminal primary amide has been deleted and the L-tryptophan replaced by a D-tryptophan are reported. These analogs e.g. BoC-Tyr(SO
3H)-NlE-Gly-XXX-Nle-Asp-R (XXX = LTrp or DTrpl R = NH-(CH
2)
2-C
6H
5, NH-CH
2-CH-(C
6H
5)
2, N(CH
3)-(CH
2)
2-C
6H
5) were evaluated
in vitro for their ability (i) to recognize the CCK receptor on rat pancreatic acini and on guinea pig brain membranes; (ii) to stimulate amylase release from rat pancreatic acini. Although previous studies suggested that the C-terminal primary amide is essential for exhibiting a full biological response on pancreatic acini, the study reported in this communication does not confirm this hypothesis.