Summary:
Amylin is a polypeptide hormone composed of 37 aminoacids, that is produced in pancreatic beta-cells, and that
was discovered in 1987. Releasing amylin into the circulation is increased postprandially, proportionally to the
amount of digested food. Daily profile of amylin plasma levels corresponds to the profile of insulin.Normal plasma
levels of amylin vary from 4 pmol/L (fasting) to 25 pmol/L (postprandially). Receptors for amylin are highly
concentrated especially in the central nervous system – area postrema and nucleus accumbens. There is a 20%
sequence homology between amylin, calcitonin and adrenomedullin and 44% homology with calcitonin gene –
related peptide.
Amylin contributes to the regulation of postprandial glycaemia by suppression of glucagon release and by
regulation of gastric emptying. Deficit os amylin is typical for diabetes mellitus type 1 or for the late stage of
diabetes type 2. Insulin resistance in obese patients is characterized by increased levels of both insulin and
amylin. Amylin decreases food intake and participates in the regulation of body weight. Some biochemical forms
of amylin cause proliferation of osteoblasts and inhibit bone resorption. Amylin modulates insulin sensitivity of
skeletal muscle, contributes to the regulation of blood pressure and causes vasodilatation.
Key words:
amylin, insulin, glucagon, diabetes mellitus
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