23Na NMR evaluation of human erythrocytes Na+/K+/CL-cotransport. A study in elderly hypertensives.
The behaviour of sodium transport systems across the cell membrane has been poorly investigated in elderly hypertension. Sodium efflux driven by Na+/K+/Cl-cotransport activity was therefore investigated (using a novel NMR-spectroscopy method) in 5 elderly hypertensive males (mean age 78 +/- 5 years) and 5 normotensive controls (mean age 79 +/- 3 years). In order to exclude any change in cotransport activity secondary to metabolic abnormalities, both patients and controls were non-obese and had normal glucose and lipid metabolisms. The Na+/K+/Cl-cotransport evaluation was performed after three months of pharmacological wash-out, under a diet containing 120 mEq of Na+/day. The resulting data showed that Na+ efflux due to outward Na+/K+/Cl-cotransport was higher in hypertensive group than in the normotensive one (0.50 +/- 0.10 mmol Na+/l cells/hr. vs 0.33 +/- 0.03 mmol Na+/l cells/hr., respectively, p < 0.05). Intracellular Na+ content was similar in both groups. At variance with previous data from the literature, our findings indicate that the Na+/K+/Cl-cotransport activity is elevated in elderly hypertensives.
Cacciafesta
M
M
Institute of I Clinica Medica, Policlinico Umberto I, Roma, Italy.
Ferri
C
C
Scuteri
A
A
Piccirillo
G
G
Bellucci
C
C
Persichino
L
L
Ariani
A
A
Marigliano
V
V
Delfini
M
M
Miccheli
A
A
D000368:Aged; D000450:Aldosterone / Q000097:blood; D001794:Blood Pressure; D002352:Carrier Proteins / Q000097:blood*; D002784:Cholesterol / Q000097:blood; D003404:Creatinine / Q000097:blood; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D006973:Hypertension / Q000097:blood*; D007328:Insulin / Q000097:blood; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D012016:Reference Values; D012083:Renin / Q000097:blood; D012964:Sodium / Q000097:blood*; D028021:Sodium-Potassium-Chloride Symporters; D014280:Triglycerides / Q000097:blood
D002352:Carrier Proteins; D007328:Insulin; D028021:Sodium-Potassium-Chloride Symporters; D014280:Triglycerides; D000450:Aldosterone; D002784:Cholesterol; D012964:Sodium; D003404:Creatinine; D012083:Renin