Effect of hyperglycemia and hyperinsulinemia on rat red blood cell insulin receptors and catecholamines: relationship with cellular ageing.

Insulin receptor activity and its relationship with catecholamines in rat young, middle aged and old red blood cells were investigated in short term (4-6) weeks and long term (6-8 months) hyperglycemia and hyperinsulinemia. Loss of insulin receptor activity is linear with cellular ageing and norepinephrine and epinephrine levels increase with age together with levels of glycosylated hemoglobin in control animals and this correlation is altered in hyperglycemia and hyperinsulinemia. These results suggest that loss of insulin receptor in cellular ageing is probably part of a more generalised alteration which is possibly brought about by glycosylation.