A second peak in uptake of gentamicin by rat kidney after cessation of treatment

Gentamicin was administered s.c. to rats once daily for 7 days at 5 mg kg−1. At the end of this period renal concentrations of gentamicin declined from day 1 to day 5 post-dosing, but showed a second peak on day 8, after which they declined again through days 16 and 22. This second peak coincided with a peak of mitotic activity in the kidney, suggesting that this organ, while recovering from gentamicin-induced damage, passes through a temporary phase during which it has increased affinity for gentamicin.