Sleep deprivation in the rat: VI. Skin changes

All rats subjected to total or paradoxical sleep deprivation by the disk apparatus developed severe ulcerative and hyperkeratotic skin lesions localized to the plantar surfaces of their paws and to their tails. Yoked control rats only occasionally developed similar appearing lesions, which were always much less severe than in deprived rats. The deprived rat lesions could not be explained by pressure, disk rotation, water immersion, infection, necrotizing vasculitis, tyrosinemia, protein deficiency, or reduced rates of mitosis. Thus, although paw and tail lesions constitute a very reliable and severe symptom of total or selective sleep deprivation in the rat that potentially could yield insights into the pathogenic mechanisms induced by sleep loss, the mediation of the lesions remains unknown.