In vivo microscopy of the hepatic microvascular system.

In vivo microscopic study of the responses of the various segments of the hepatic microvascular system to adrenergic, cholinergic, and other aminergic substances and their antagonists have revealed the relative distribution of receptor sites in these various vessels. The results also suggest a possible interaction of cholinergic substances with periportal mast cells. The release of serotonin, histamine and possibly other products from these cells results in dramatic alterations in blood flow through the hepatic sinusoids due to the adhesion of leukocytes and platelets to the endothelium.