EARLY NEPHROTOXICITY AT HIGH PLASMA-CONCENTRATIONS OF LYSOZYME IN THE RAT

  • 1 January 1982
    • journal article
    • research article
    • Vol. 46  (2) , 149-157
Abstract
In clearance experiments, egg white lysozyme was i.v. infused into male Wistar and Wistar/Furth rats over different periods of time to achieve plasma concentrations of lysozyme in the range of 30-8000 .mu.g/ml. The glomerular filtration rate and the appearance of glomerular and tubular epithelia were comparable to those of control rats < 3000 .mu.g/ml plasma concentration of lysozyme and up to 60 min infusion time when investigated by scanning electron microscopy. A 50% drop in blood pressure occurred at a plasma lysozyme concentration of 3000 .mu.g/ml which was prevented by the i.v. injection of an antihistamine or by using Wistar/Furth rats; the decrease of the glomerular filtration rate and of the fractional lysozyme reabsorption and the increase of Na and K excretion could not be avoided. After 30 min of lysozyme infusion, the epithelial foot processes exhibited slight regional effacement and in > 50% of the tubules protein cast formation was noted. Occurrence of foot process effacement and tubular casts increased with further increase of plasma lysozyme concentration and lysozyme infusion time. These morphologic changes were common for Wistar rats, antihistamine-pretreated Wistar rats, Wistar/Furth rats and in situ-perfused rat kidneys. The cationic low MW protein lysozyme induced functional and structural alterations that were correlated with plasma lysozyme concentration and lysozyme infusion time and caused acute renal failure.