Effect of high salt intake on sodium, potassium-dependent adenosine triphosphatase activity in the erythrocytes of normotensive men.
1. We measured ouabain-insensitive adenosine triphosphatase (ATPase), sodium, potassium-dependent adenosine triphosphatase (Na+,K+-ATPase) and intracellular Na+ and K+ in the erythrocytes of 19 healthy volunteers, before and after supplementation of their normal diet was 6.0-8.9 g of salt (102-137 mmol of NaCl) per day, for 5 days. 2. The subjects had a small but significant gain in weight. Mean plasma renin activity decreased from 1.57 to 0.73 pmol of angiotensin 1 h-1 ml-1 and plasma aldosterone from 0.46 to 0.24 nmol/l. 3. Total ATPase activity fell from 197.9 nmol of inorganic phosphate h-1 mg-1 during the control period to 173.5 during the high-salt period (P less than 0.0125). Na+, K+-ATPase activity fell from 162.2 to 141.4 nmol of inorganic phosphate h-1 mg-1 (P less than 0.05). Intracellular Na+ and intracellular K+ did not change. 4. These results are consistent with the hypothesis that salt-induced volume expansion causes the release of a factor inhibitory to the Na+ pump.
Quintanilla
A P
AP
Section of Nephrology/Hypertension, Veterans Administration Lakeside Medical Center, Chicago, IL 60611.
Weffer
M I
MI
Koh
H
H
Rahman
M
M
Molteni
A
A
del Greco
F
F
D000328:Adult; D000450:Aldosterone / Q000097:blood; D001794:Blood Pressure; D001835:Body Weight; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D008297:Male; D011187:Posture; D011188:Potassium / Q000097:blood; D012083:Renin / Q000097:blood; D012964:Sodium / Q000097:blood; D012982:Sodium, Dietary / Q000008:administration & dosage / Q000494:pharmacology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000097:blood*
D012982:Sodium, Dietary; D000450:Aldosterone; D012964:Sodium; D012083:Renin; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium