The influence of glucose-induced hyperinsulinaemia on renal glomerular function and circulating catecholamines in normal man

The circulatory, renal, and hormonal responses to physiological elevation of plasma insulin induced with oral glucose have been studied in seven healthy subjects. glomerular filtration rate, urinary excretion rates of albumin and Beta2-microglobulin, haematocrit, pulse rate, blood pressure and plasma catecholamine concentrations have been measured. Physiological hyperinsulinaemia following glucose ingestion was associated with an increase in noradrenaline levels and brief tachycardia. No effect was noted on haematocrit, creatinine clearance, urinary albumin excretion, plasma adrenaline concentrations and arterial blood pressure. Urinary Beta2-microglobulin excretion rates fell shortly after the elevation of plasma insulin, probably indicating enhanced tubular reabsorption. Thus, glucose-induced physiological hyperinsulinaemia does not reduce glomerular filtration rate nor does it increase transglomerular passage of albumin, effects seen after the intravenous bolus injection of 6-8 U of insulin in diabetics.