The effects of variable dietary
thiamine concentrations (deficient, normal, surplus) on the development of alcoholic neuromyopathy in rats exposed for 36 weeks to 10-25% (v/v)
ethanol or water (control group) as the sole drinking fluid were studied by histological and electrophysiological methods. Abnormalities in the structure of the sciatic nerve (phagocytosis, myelin abnormalities, increase in nonspecific
cholinesterase activity) and tibial muscles (angular atrophic fibers, group
atrophy, fibre
necrosis) developed more frequently in animals on diets deficient in
thiamine than in animals on diets with normal or surplus
thiamine, and more frequently in animals drinking alcohol and water than in those
drinking water alone. No differences were observed between the different groups in the number of perivascular sympathetic nerves, in the motor nerve conduction velocities and in the muscle fibrillation potentials. Thus,
thiamine deficiency, established as a significant reduction of red blood cell
transketolase activity, seems to have a deleterious effect on the peripheral nerves and muscles. The effect is enhanced by the simultaneous consumption of
ethyl alcohol.