Ultrastructural changes in limb distal nerves of rats with alcoholism and/or malnutrition before and after dietary correction.

To study peripheral nerves changes in chronic alcoholism and in malnutrition, we examined ultrastructurally the distal nerve branches of the digits of rats treated with four different dietary schemes, as follows: controls (n = 22), fed standard rodent diet plus water ad libitum; alcoholism (n = 12), fed the standard diet and 2-12% ethanol in drinking water; malnutrition (n = 21), fed with corn tortillas instead of standard diet; and alcoholism and malnutrition combined (n = 22). After 10 months under these conditions, a proportion of animals from each group were sacrificed. The remaining rats of the malnutrition and alcoholism alone groups were deferred a standard diet. The combined alcohol + malnutrition group was subdivided into standard diet, malnutrition and ethanol. After a further 4 months under these new conditions, the animals were sacrificed. Ultrastructural examination of limb distal nerve branches showed that glycogen-like particles were more common in malnourished animals, whereas remyelinating axons were more numerous in ethanol-treated rats. Bands of regeneration were present in both groups, but were more common in animals treated with ethanol. These features decreased significantly when the respective nutritional factor was reversed. The results confirm that ethanol plays a definitive role in the development of alcoholic neuropathy and that malnutrition accentuates, the histopathological abnormalities.