AJP - Renal Physiology, Vol 249, Issue 6 832-F835, Copyright © 1985 by American Physiological Society
Modification of experimental gentamicin nephrotoxicity by selective parathyroidectomy
W. M. Bennett, J. P. Pulliam, G. A. Porter and D. C. Houghton
Dietary calcium loading reduces gentamicin nephrotoxicity in rats. Since
parathyroid hormone increases renal brush border membrane anionic
phospholipids, the putative gentamicin receptors, the effects of selective
parathyroidectomy on gentamicin nephrotoxicity were examined. Male Fisher
344 rats underwent parathyroidectomy or sham surgery. All animals were fed
a diet containing 0.5% calcium for 2 wk prior to gentamicin, 20 mg/kg twice
daily for 6 and 10 days. Other parathyroidectomized rats were fed a 4%
calcium diet for 2 wk and treated similarly with gentamicin On day 6, serum
creatinine (mg/100 ml) was 2.0 +/- 0.9 in the sham-operated animals, 1.7
+/- 1.6 in the parathyroidectomized animals on the 0.5% diet, and 0.8 +/-
0.1 in the parathyroidectomized animals on the 4% diet. By 10 days, the
sham-operated animals had creatinine values of 6.3 +/- 1.6 (mg/100 ml)
compared with 1.7 +/- .9 in the parathyroidectomized animals on the same
diet and 0.8 +/- 0.2 in the 4% diet animals. More severe tubular necrosis
was present in the sham-operated compared with the parathyroidectomized
animals. High calcium diet in the parathyroidectomized animals produced
structural and functional protection from gentamicin nephrotoxicity. Human
parathyroid hormone (1-34) 20 IU twice daily given subcutaneously to a
separate group of parathyroidectomized rats, eliminated the protective
effect of parathyroidectomy on renal structure and function.
Parathyroidectomy modifies experimental gentamicin nephrotoxicity. The
additional protective effect of dietary calcium loading may be independent
of parathyroid ablation.
