AJP - Renal Physiology, Vol 252, Issue 2 310-F316, Copyright © 1987 by American Physiological Society
Effect of bicarbonate and phosphate on renal phosphate leak in experimental Fanconi syndrome
Y. Shvil, H. Wald and M. M. Popovtzer
The role of acidosis in the renal phosphate leak in Fanconi syndrome (FS)
was studied in maleate-induced FS in rats. Clearance studies were performed
in the following groups: 1) intact rats served as control, 2) rats with
maleate-induced FS, 3) rats with FS receiving intravenous bicarbonate
(HCO3-), 4) intact rats receiving intravenous 0.03 N HCl (inducing acidosis
similar to that of Group 2), 5) rats with FS receiving intravenous
phosphate buffer and NaCl, and 6) rats with FS receiving intravenous
phosphate buffer and bicarbonate similar to Group 3. In Group 2 serum pH
and fractional excretion of phosphate (CP/GFR) averaged 7.31 +/- 0.08 (mean
+/- SE) and 1.00 +/- 0.06, respectively, and differed significantly from
Group 1, in which the corresponding values were 7.41 +/- 0.01 and 0.12 +/-
0.02, respectively. In Group 3, intravenous HCO3- corrected pH to 7.43 +/-
0.01 and reduced CP/GFR to 0.33 +/- 0.05, both results were different from
the corresponding rates in Group 2 (P less than 0.0005). In Group 4,
intravenous HCl reduced serum pH to 7.31 +/- 0.02 (P not significant as
compared with Group 2) and increased CP/GFR to 0.186 +/- 0.030, the latter
was higher than CP/GFR in control rats (P less than 0.01) but was lower
than that in HCO3- -treated FS rats. In Group 5 serum pH was 7.31 +/-
0.021, similar to Group 2. CP/GFR was 0.84 +/- 0.031, significantly lower
than in Group 2 (P less than 0.05). In Group 6 serum pH was 7.43 +/- 0.013
and CP/GFR was 0.86 +/- 0.044.(ABSTRACT TRUNCATED AT 250 WORDS)
