Depressed eruption dental rate in rats with hemodynamically-mediated acute renal failure

The effects of acute renal failure on the impeded (IER) and unimpeded (UER) eruption dental rate and attrition rate (AR) were investigated. Adult female Wistar rats were injected with 125 mg/kg b.w of human methemoglobin (M-Hb) in order to induce a first episode of hemodynamically-mediated acute renal failure (H-ARF). Ten days after the injection of M-Hb, other groups of rats received another equal dose of the drug in order to induce a second episode of H-ARF. A group of six animals was pair-fed daily and individually with rats of M-Hb groups. Evaluation of renal function, histopathology studies, IER, UER, food intake (FI), AR and body weight gains was performed at different times after the first and second injections, of M-Hb. Treatment induced transient increases in plasma urea concentration and urine volume, and significant depression in urine osmolality, body weight gains, IER, UER and AR. In every case, the maximal effect of the first injection of M-Hb on the individual parameters was always greater than that of the second injection. Histologic sections showed interstitial cellular infiltration, desquamation of the proximal tubular epithelium and collapse or dilation of the tubular lumen. The functional values of kidney, histologic findings, IER, UER and AR of the pair-fed rats were not significantly different from control values. The results of the present study indicate that dental eruption rate (IER and UER) is relatively low in uremic rats with kidney tubule lesions and that both parameters are related.