ALPHA-TOCOPHEROL ATTENUATES ETHANOL-INDUCED INHIBITION OF THE RAT HEMI-DIAPHRAGM CONTRACTION

Ethanol treatment has been reported to increase the production of oxyg en-derived free radicals which contribute to the development of skelet al muscle injury. The possible protective effect of alpha-tocopherol o n the ethanol-induced inhibition of the rat hemi-diaphragm contraction was investigated in vitro. Ethanol (3.7 g kg(-1), po) given chronical ly for 1 or 2 weeks significantly decreased both the direct and indire ct contractions of the diaphragm muscle. Administration of alpha-tocop herol (600 mg kg-l, im) for 1 or 2 weeks abolished the inhibitory effe cts of ethanol on the skeletal muscle. Additionally, alpha-tocopherol (600 mg kg(-1) im) reversed the decrease in time (s) of the 50% decrea se in the height of contraction of the indirect responses of the rat h emi-diaphragm preparation. In conclusion, alpha-tocopherol reverses th e inhibitory effects of chronic ethanol treatment on both the direct a nd indirect contractions of the rat hemidiaphragm muscle.