Stimulation of kidney function in rats of different ages injured by nephrotoxic agents

Intensity and duration of nephrotoxic effects can be characterized by measurement of renal p-aminohippurate (PAH) excretion. Single administration of potassium dichromate or glycerol is followed by a marked decrease of renal PAH excretion in dependence on the time after the administration as well as on the dosage used. Both agents are without effect in young rats with an immature tubular transport system for organic anions. As observed previously in rats with intact kidney function, renal PAH excretion can also be stimulated in rats with potassium dichromate or glycerol induced kidney damage. Stimulation of renal PAH excretion is possible in injured rats by repeated administrations of PAH and cyclopenthiazide, respectively. Exactly, the duration of injury is shortened whereas the intensity of the nephrotoxic effect is not changed. However, this effect depends on the age of rats as well as on the nephrotoxic agent administered.