Renal Regulation of Acid-Base Balance in the Chicken

Abstract

Experimental acidosis in the chicken, produced by HC1 infusion results in a fall in urinary pH, to a lower limit about 4.7. Simultaneously the excretion of titratable acid and ammonia increased to maximum values of 3m eq/kg/min. for each. In this case, titratable acid is chiefly uric acid, monobasic phosphate comprising less than 1/3 of the total. Further increases in titratable acid excretion, to 10m eq/kg/min., follows the infusion of neutral phosphate or urate solutions, as these provide more buffer for acidification by the renal tubules. Excretion of ammonia can be increased independent of urinary pH by the infusion of such amino acids as glycine, leucine, and alanine. As in mammals, inhibition of carbonic anhydrase with No. 6063 (2-acetylamino, 3,4-thia-diazole, 5-sulfonamide) markedly reduces the capacity of the kidney to acidify urine.