Effects of 5-hydroxytryptamine and related agents on endothelial cell oxidative metabolism in vitro.
A recently described microrespirometric method was used to determine the influence of 5-hydroxytryptamine (5-HT), nialamide, imipramine and ouabain alone and in combinations on oxidative metabolism in monolayer cultures of endothelial cells from the rat pulmonary artery. It was found that exposure to 5-HT increased oxygen uptake in the cultures, while imipramine or ouabain decreased respiration; nialamide had no obvious effect. When used in combinations, the effect of ouabain or imipramine dominated over the 5-HT effect. The explanation for this 5-HT stimulating effect on endothelial cell oxidative metabolism, previously undescribed, is suggested to be that 5-HT exposure stimulated individual cells to contract. This active contraction resulted in an increased energy demand reflected in elevated oxygen consumption, an effect inhibited by ouabain or imipramine.
D000818:Animals; D002478:Cells, Cultured; D004727:Endothelium / Q000187:drug effects / Q000378:metabolism*; D007099:Imipramine / Q000494:pharmacology; D009526:Nialamide / Q000494:pharmacology; D010042:Ouabain / Q000494:pharmacology; D010084:Oxidation-Reduction / Q000187:drug effects; D010101:Oxygen Consumption / Q000187:drug effects*; D011651:Pulmonary Artery / Q000378:metabolism*; D051381:Rats; D012701:Serotonin / Q000494:pharmacology*; D013147:Spirometry / Q000379:methods
D012701:Serotonin; D010042:Ouabain; D007099:Imipramine; D009526:Nialamide