The effect of atrial natriuretic peptide on acid-base balance in rats with chronic renal failure.
We explored the effects of 12-hour infusion of atrial natriuretic peptide (alpha-rANP:rat, 1-28) on arterial acid-base balance, using 5/6 nephrectomized rats with chronic renal failure. Before the infusion, nephrectomized rats had a higher mean arterial blood pressure, greater urine volume, and lower creatinine clearance than the normal controls, but they did not show a significant difference in arterial hydrogen ion concentration (pH), plasma bicarbonate concentration (HCO3-), partial pressure of carbon dioxide (PCO2), plasma base excess (BE), or plasma ANP concentration. alpha-rANP infusion produced a continuous blood pressure reduction in both nephrectomized and control rats. Urine volume and urinary sodium and potassium excretion tended to increase at 2-hour infusion, but not at 12-hour infusion. In the controls alpha-rANP significantly increased pH from 7.47 to 7.50, and decreased PCO2 by 14%. In contrast, in nephrectomized rats alpha-rANP significantly decreased pH from 7.48 to 7.44, HCO3- by 13%, and BE from -0.07 to -3.22 meq/l. Rats with chronic renal failure had greater reduction in HCO3- than the controls (p less than 0.05). There was no difference in plasma ANP level between the two groups. Thus, it is indicated that the long-term infusion of alpha-rANP reduces pH in rats with chronic renal failure, thereby adversely affecting the acid-base balance.
Kusaka
M
M
Department of Medicine, Dokkyo University School of Medicine, Tochigi, Japan.
Atarashi
K
K
Numabe
A
A
Baba
Y
Y
Shinozaki
K
K
Uehara
Y
Y
Yagi
S
S
Hirata
Y
Y
Ishii
M
M
D000136:Acid-Base Equilibrium / Q000187:drug effects*; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D003404:Creatinine / Q000097:blood; D004231:Diuresis / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D007676:Kidney Failure, Chronic / Q000503:physiopathology*; D008297:Male; D011188:Potassium / Q000097:blood; D051381:Rats; D012964:Sodium / Q000097:blood
D009320:Atrial Natriuretic Factor; D012964:Sodium; D003404:Creatinine; D011188:Potassium