Summary
Moderate alcohol consumption has been shown to reduce the risk of ischemic heart disease
potentially through its effect on specific endothelial-derived compounds. We tested
the hypothesis that ethanol increases the expression of endothelial nitric oxide synthase
(eNOS) and nitric oxide (NO) production in bovine aortic endothelial cells (BAEC).
Primary cultures of BAEC grown to confluence under standard conditions were treated
3-6 h with 0.1% ethanol in the presence of indomethacin. Ethanol induced a significant
increase in both basal and stimulated NO production as determined by chemiluminescence
method. This effect was accompanied by a rapid increase of eNOS protein and mRNA expression
levels. eNOS mRNA increased two-fold within 3 h and gradually declined, but the increased
levels of mRNA persisted for >24 h. A similar increase of eNOS expression was observed
in human umbilical endothelial cells exposed to ethanol. These results demonstrate
that ethanol augments both basal and stimulated NO production and that this effect
is associated with increased eNOS protein and mRNA expression levels. The data are
consistent with the hypothesis that the reduced incidence of ischemic heart disease
associated with alcohol may be related, at least in part, to the modulation of vascular
endothelial cell production of NO