Renal pharmacokinetics of furosemide in young and adult rats.
In rats of different ages the furosemide concentration in the kidney was measured at different times after the administration of 0.6 mg/100 g b. wt. furosemide i.p. The accumulation of furosemide was studied on renal cortical slices. The maximal concentration of furosemide in kidney tissue can be reached more rapidly in 55-day-old rats than in 5-day-old rats. There are no differences in medullar and cortical concentrations of furosemide in the kidney. In the renal cortical slices from 55-day-old rats the accumulation of furosemide against the medium is 4 to 6.6 fold in dependence on the initial concentration in the medium. In contrast to experiments with PAH, the accumulation of furosemide is reduced though not abolished in a N(2-)atmosphere. Renal cortical slices from 5-day-old rats cannot accumulate furosemide. The efflux of furosemide and PAH, respectively, from renal cortical slices from 55-day-old rats is not different. The data are discussed in connection with previous results on the age dependence of pharmacokinetics and efficiency of furosemide.
D000375:Aging; D000818:Animals; D005665:Furosemide / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism; D007700:Kinetics; D008297:Male; D011817:Rabbits; D051381:Rats; D010130:p-Aminohippuric Acid / Q000378:metabolism
D005665:Furosemide; D010130:p-Aminohippuric Acid