In-utero gentamicin-induced nephrotoxicity in rats.

Aminosides lead to a well-known nephrotoxicity. The possibility of the developing kidney being altered in utero after the pregnant mother's administration has been investigated. We gave gentamicin (75 mg/kg/day) to pregnant rats during periods of organogenesis (days 7-11) and the beginning of glomeruli differentiation (days 14-18). A group of nonpregnant females was also treated for the same period and at the same time each day. Gentamicin-treated mothers presented only minor modifications of the blood biology with no acute renal failure when treated nonpregnant females have a hypercreatininemia. The deep cortical area, containing the fully formed nephrons of neonates, presented less glomeruli that were differentiated in the gentamicin group than in the control group. Moreover with both light and electron microscopy, glomeruli and proximal tubules showed evidences of nephrotoxicity in the juxtamedullary cortex. This finding of an in utero aminoside nephrotoxicity demonstrates the possible toxicity of gentamicin on fetus kidneys when given during the pregnancy.