Effect of Gd-DTPA on Kidneys of the Rats with Acute Renal Failure

Jung, Jung Im; Park, Seog Hee

Abstract

PURPOSE
To evaluate the nephrotoxicity of Gd-DTPA in rats with normal renal function and in those with acute renal failure, using 0.1mmol/kg and 0.3mmol/kg in each group.
MATERIALS AND METHODS
Sixty rats weighing 200-250gm were divided into two groups: normal (N) and glycerol induced acute renal failure (F) ; this was inducedby intramuscular injection of 50% glycerol(10ml/kg). Each group was divided into three subgroups; subgroup 1 was given physiologic saline (0.15 M NaCl) via the tail vein, while subgroups 2 and 3 were given 0.1 mmol/kg Gd-DTPAand 0.3mmol/kg Gd-DTPA, respectively. Blood and 24-hour urine were collected before and on the first and secondday after intravenous injection of either physiologic saline or Gd-DTPA. In order to obtain pathologic specimens, two additional rats in each group underwent the same experimental procedure, and on the first or second day after intravenous injection of saline or Gd-DTPA, both kidneys were removed for light microscopic examination. Serum creatinine (Cr), urine creatinine, and several urinary enzymes such as alkaline phosphatase (ALP), gammaglutamyl transferase (GGT), N-acetyl-Beta-glucosaminidase (Beta-NAG) and lactic dehydrogenase (LDH) of 24 hour urine were measured, and creatinine clearance (Ccr) was calculated.
RESULTS
The results were as follows. 1. In the groupwith normal renal function, levels of serum creatinine and urinary enzymes remained unchanged after infusion of 0.1mmol/kg Gd-DTPA or 0.3mmol/kg Gd-DTPA. 2. Among rats with acute renal failure, no difference in serum creatinine and urinary enzyme levels between the saline injection group and 0.1mmol/kg Gd-DTPA injection group was noted. 3. Among rats with acute uremia, Beta-NAG, LDH and ALP were significantly higher on post-injection days 1 and 2 in the 0.3mmol/kg Gd-DTPA injection group than in the physiologic saline or 0.1mmol/kg Gd-DTPA injection group.4. Light microscopic exammination of rats with normal renal function after Gd-DTPA injection revealed no significant pathologic change. Those with acute renal failure rats revealed some degree of vacuolization and/or necrosis of renal proximal tubular epithelial cells. No difference was found, however, between the saline and Gd-DTPA injection subgroups.
CONCLUSION
In conclusion, Gd-DTPA was safe in rats with normal renal function, even when the dose was tripled (0.3mmol/kg), and was safe in those with acute renal failure when the standard dose (0.1mmol/kg) was given. In this latter group, however, a triple dose induced some renal damage.