We have previously shown that the rat with experimental diabetes (DM) of 4-6 months' duration exhibits complete functional and morphologic protection against
gentamicin-induced
acute renal failure. To assess the role of the duration of the diabetic state per se on the resistance to
gentamicin, female Sprague-Dawley rats with diabetes of short (5 days, n = 7), intermediate (5 weeks, n = 5) and long duration (5 months, n = 7) were studied. Diabetes was induced by
streptozotocin, 50-65 mg/kg b.w. i.v. Controls were identically treated sex- and age matched nondiabetic rats. The animals were kept in individual metabolic cages for 2 weeks and all received
gentamicin 40 mg/kg/day for 9 days.
Sham animals (DM and control) received
Ringer's solution in place of
gentamicin. Prior to
gentamicin, plasma
glucose levels and
creatinine clearances (Ccr) were higher in the DM long duration group (619 +/- 25 (SE) mg/dl; 2.6 +/- 0.2 ml/min, respectively) than in the DM short (514 +/- 24; 2.0 +/- 0.1) and DM intermediate duration (442 +/- 30; 2.1 +/- 0.1) groups, while urine volume and
glycosuria were similar. Following
gentamicin the three control groups developed
acute renal failure (maximal decrease in Ccr of 60 +/- 7, 72 +/- 9 and 71 +/- 7%, respectively; p less than 0.01 to less than 0.001), lysozymuria and acute tubular
necrosis. There were no significant differences in the degree of renal impairment observed among the three control groups. In marked contrast, in the three DM groups these changes were absent and the renal cortical
gentamicin content was lower than that of the control groups.(ABSTRACT TRUNCATED AT 250 WORDS)