Circulatory effects of somatostatin in anesthetized man

The effect of intravenous somatostatin (1 microgram.kg-1 over 1 min) on arterial pressure and on the blood flow to various splanchnic organs, skeletal muscle and brain tissue was studied by means of electromagnetic blood flow measurements in patients undergoing abdominal surgery or reconstructive surgery of the internal carotid artery. Somatostatin infusion reduced the blood flow in the common hepatic artery by 56%, in the splenic artery by 26%, in the ileocolic artery by 34% and in the left colic artery by 36%. External iliac artery blood flow was increased by 43% while internal carotid artery blood flow was unchanged. Mean arterial pressure was increased by 20%. It is suggested that these circulatory effects of somatostatin are due to a direct effect of somatostatin on vascular smooth muscle.