Nerve fibre degeneration of the central and peripheral nervous systems in severe protein deprivation in rats.

Knowledge from previous reports that kwashiorkor in man may lead to nerve fibre degeneration prompted this study on rats. The rats were subjected to severe protein deprivation from 6 weeks of age. Protein deprivation was achieved by feeding the rats ad lib with a diet containing only 1.5% protein. Control rats received an iso-caloric diet with 14% protein. The vitamin content in both diets was well above normal requirements. In relation to body weight the protein-deprived rats did not consume less food than the control rats. Protein deprivation resulted in stunted body growth, markedly reduced values of serum albumin, and changes in the fur accompanied by areas of alopecia. Furthermore, the protein-deprived rats showed degeneration of nerve fibres in the medial parts of the posterior columns of the cervical but not the sacral part of the spinal cord and nerve fibre degeneration in the distal but not the proximal parts of the longitudinal tail nerves. Teased nerve fibre preparations of the tail nerves revealed changes consistent with the Wallerian type of degeneration. It is concluded that severe protein deprivation in young rats may lead to a "dying-back" type of neuropathy in the central and peripheral nervous systems.