[Studies of the effect of gentamicin on the kidneys of healthy young rats. II. Studies of renal parenchyma of experimental animals in the light and electron microscopy after gentamicin load].

Gentamicin was given to rats in the doses and intervals equivalent to those used in patients. This resulted in the morphologic changes in the animal kidneys. The severity of them was directly related to the dose of antibiotic. The morphologic changes--vacuolar degeneration in the epithelial cells of the proximal tubule, the inflammatory infiltrates in the interstitial tissue and the increased number of lysosomes with myelinic structures as well as mitochondrial oedema, the increased number of peroxysomes in the epithelial cells of the proximal tubules indicate the toxic influence of gentamicin on the proximal tubule. The disappearance of the morphologic and functional changes after the withdrawal of gentamicin indicates reversibility of them.