In rats, neither acute administration of ethanol nor the establishment of ethanol dependence by chronic administration for 28 days produced significant 1H-NMR relaxation changes. However, chronic ethanol intake for six months produced a transient rise in T1, with no change in T2 or water content. The significance of these results for study in man is discussed and a hypothesis is proposed to explain discrepant differences between T1, T2 and water content. It is suggested that T1 change with long-term ethanol exposure is related to altered free/bound water state secondary to cell membrane changes.