1. In vivo and in vitro effects of amylin and amylin-amide on calcium metabolism in the rat and rabbit.
- Author
-
Datta HK, Zaidi M, Wimalawansa SJ, Ghatei MA, Beacham JL, Bloom SR, and MacIntyre I
- Subjects
- Animals, Bone Resorption drug effects, Calcitonin pharmacology, Calcitonin Gene-Related Peptide, Humans, Islet Amyloid Polypeptide, Kinetics, Male, Microscopy, Electron, Scanning, Neuropeptides pharmacology, Osteoclasts drug effects, Osteoclasts physiology, Rabbits, Rats, Rats, Inbred Strains, Amyloid pharmacology, Calcium blood
- Abstract
Amylin is a new member of the calcitonin/CGRP family: it is a 37 amino acid polypeptide which was recently isolated from amyloid deposits in pancreatic islets obtained from type II diabetics. In the present study we investigated the effect of amylin and amylin-amide on calcium metabolism in the rat and rabbit. Two main methods were used: in vivo hypocalcaemic activity was assessed by measuring plasma calcium levels after injection of the peptide in 50 g rats; and in vitro resorption of cortical bone by disaggregated rat osteoclasts was quantified by scanning electron microscopy together with image analysis. We demonstrate that amylin and amylin-amide have calcitonin-like effects: both are powerful inhibitors of osteoclastic resorption and as a consequence lower plasma calcium in both rats and rabbits. We speculate that the peptide may exert systemic or local regulatory effects on bone cells.
- Published
- 1989
- Full Text
- View/download PDF