Structure of insulin
Insulin is composed of two peptide chains (A and B, 21 and 30 amino acids long respectively) connected to each other by two disulphide brides from cysteine groups.
Function of insulin
Resistance to insulin develops in elderly people. Their tissues no longer respond as well to insulin as they did previously. The consequences of this resistance firstly include an increase in insulin concentrations in the blood (which may appear paradoxical but is entirely logical) and secondly the development of metabolic disorders which predispose to accumulation of fat, which in turn contributes to deterioration of the arterial wall. Treatment of this type of dysfunction is one of the major research subjects into the effects of ageing and all the more so as it is currently only partly treated locally.