Production and metabolism of dopamine and norepinephrine in mesenteric organs and liver of swine

norepinephrine in mesenteric organs and liver of swine. Am. J. Physiol. 268 (Gastrointest. Liver Physiol. 31): G641-G649, 1995.-Concentrations of catecholamines and their metabo-lites in plasma entering and exiting mesenteric organs, liver, and kidneys were examined to assess the regional production and metabolism of catecholamines in anesthetized swine. Higher portal venous than arterial plasma concentrations of norepinephrine and its metabolites, 3,4-dihydroxyphenylgly-co1 (DHPG) and 3-methoxy-4-hydroxyphenylglycol (MHPG), and of dopamine and its metabolites, 3,4-dihydroxyphenylace-tic acid (DOPAC) and homovanillic acid (HVA), indicated substantial production of both catecholamines by mesenteric organs, representing 4550 % of total body production. Most dopamine was not metabolized to norepinephrine, suggesting a large nonnoradrenergic contribution to total body dopamin