Intraperitoneal Injection Of Gentamicin Research Articles

The protective effect of nitrendipine on gentamicin acute renal failure in rats

Aminoglycoside nephrotoxicity was produced in two groups of Fischer rats by intraperitoneal injection of gentamicin, 40 mg/kg/day for 2 weeks. Beginning 3 days prior to, and continuing throughout the 2-week treatment period, one of the groups (control) received the inert vehicle, polyethylene glycol, while the experimental group was given nitrendipine, a calcium channel blocker, in a dose of 25 mg/kg/day by gavage. Both groups received food and water ad libitum. Gentamicin with vehicle caused a marked decrease in inulin clearance (4.9 ml/min/kg) and paraaminohippurate (PAH) extraction (26%), and extensive renal tubular necrosis. In comparison, the nitrendipine-treated rats had a significantly increased clearance (9.8 ml/min/kg) and PAH extraction (48%), and less histopathologic damage. Renal tissue content of gentamicin was not influenced by nitrendipine after 4 days of dosing. Nitrendipine, a diisopyridine derived calcium channel blocker, offers significant functional and histologic protection against aminoglycoside nephrotoxicity in Fischer rats. Its mode of action in this regard is unknown.

Maturation of renal tubular transport of gentamicin.

Previous data have suggested an age-related increase in renal clearance of gentamicin. This phenomenon could be the result of an increase in glomerular filtration rate (GFR) and/or of an augmentation in its transtubular influx. To investigate this question, four groups of rats, 2, 4, 6 and 8 weeks old, were sacrificed. 125I-labeled gentamicin uptake was measured in renal cortical slices as the cpm/mg wet tissue slice/medium (S/M) ratio. There was a significant age-related increment in gentamicin uptake. S/M ratios at 2, 4, 6 and 8 weeks were 3.49 +/- 0.46 (n = 7), 3.52 +/- 0.37 (n = 10), 4.23 +/- 0.42 (n = 10), 4.81 +/- 0.45 (n = 17), respectively (mean +/- SD; r = 0.78; p less than 0.01). Intraperitoneal injections of gentamicin were administered to another group of rats for 10 consecutive days from age 2 weeks and more. Gentamicin uptake of their renal cortical slices at 6 weeks of age was similar to that observed in the parallel age group of the nonstimulated rats (S/M ratio 4.18 +/- 0.41).