[Pharmacokinetics and nephrotoxicity of aluminum in rats of various ages]

Experiments were done in 5-, 10-, 20-, 33-, 55-, and 105-d-old rats to clarify whether or not age-dependent differences in pharmacokinetics and nephrotoxicity of Al exist. Using kidney function tests distinct signs of alumina (Al) nephrotoxicity can be demonstrated following 1 or 2 mg Al/100 g b. wt. i.p.: polyruria, reduced concentration of sodium in urine, elevated blood urea nitrogen concentrations. There is the same degree of nephrotoxicity both in adult and in young rats with an immature kidney function. Following administration of 2 mg Al/100 g b. wt. i. p. the initial plasma concentration of Al is distinctly lower in young than in adult rats. A rapid phase of elimination of Al from plasma (alpha-slope) is absent in 5-d-old rats and fully expressed in 33- and 55-d-old rats. In young rats the relative volume of distribution of Al is smaller than in adults. Following the administered dose nephrotoxicity in ducing concentrations of Al were obviously reached also in kidney tissue of young rats.