The effect of standing and exercise on plasma catecholamines, serum insulin, and serum gastrin

Glucose-stimulated insulin secretion was measured in six normal subjects in the resting supine position, during standing, and during a period of moderate exercise in the supine position. Plasma noradrenaline averaged 0.26 ng/ml in the supine, resting position and rose to 0.57 and 0.61 ng/ml at the end of the standing experiment and the exercise period, respectively. Plasma adrenaline was unchanged in the standing position but rose threefold during exercise (to 0.09 ng/ml). Serum gastrin tended to decrease in all three experiments after the injection of glucose. Glucose-stimulated insulin secretion was the same during the first 10 min after the injection of glucose in the three experiments. It is concluded that a moderate increase in adrenergic activity has no influence on glucose-stimulated insulin secretion.