Morphological study of the kidneys of lithium treated rats.

Short-term treatment of rats with low doses (2 meq/kg) of lithium carbonate led to renal damage which, however, appeared to be almost completely reversible even in nephrectomized animals. Renal damage caused by higher doses (6 meq/kg) was more explicit, but also appeared to be reversible to a certain degree even in the case of continuous lithium treatment. Regeneration was less expressed in nephrectomized animals. The collecting tubules and some segments of Henle's loop, as sites poor in mitochondria, display increased susceptibility to the damaging effect of lithium carbonate.