Korean J Physiol Pharmacol.
2001 Feb;5(1):47-53.
Pulse exposure to ethanol augments vascular contractility through
stress response
- Affiliations
-
- 1Department of Pharmacology, Kyungpook National University School of
Medicine, 101 Dongin-2-Ga, Taegu, South Korea. inkim@knu.ac.kr
Abstract
- Drinking excessive alcohol has been recognized as a risk factor for
hypertension. However, the mechanism by which alcohol intake causes
hypertension still remains elusive. We tested the hypothesis that
ethanol itself acts as a stress factor on vasculature and indirectly
modulates vascular contractility. After end of exposure to 1, 2.5 and
5% ethanol for 45 min, rat aortic strips were subjected to contractile
responses, immunoblot for Hsp70 and the measurement of levels of myosin
light chain phosphorylation. Exposure to 5% ethanol not only augmented
contractions to KCl or phenylephrine, but also increased expression of
Hsp70 and the levels of myosin light chain phosphorylation. There were
no significant differences in contractions produced by 1 micromol/L
phorbol 12,13-dibutyrate, a protein kinase C activator, whether the
tissues were exposed to 5% ethanol or not. This is the first report to
show that even short exposure to ethanol has a delayed effect to
increase vascular smooth muscle contractility through a modulation of
thick filament regulation. It may be a mechanism by which ingestion of
alcohol induces hypertension.