Erythrocyte Na+, K+ and Ca2+, Mg(2+)-ATPase activities in hypertensives on angiotensin-converting enzyme inhibitors.
OBJECTIVE
To investigate erythrocyte membrane Na+, K(+)- and Ca2+, Mg(2+)-ATPase activities in newly diagnosed hypertensive patients before and after 2, 4, and 6 months of treatment with enalapril or captopril as monotherapy.


RESULTS
Na+, K(+)-ATPase activity (nmol ATP hydrolysed/min per mg protein) rose by 6 months of treatment in both groups when values were compared in each treated group over time (4.5 +/- 0.8 to 9.9 +/- 1.2; 4.9 +/- 0.8 to 10.5 +/- 1.7, respectively, p < 0.001 for both). When the treated groups were compared with controls at each period of time, Na+, K(+)-ATPase activity was higher at months 4 and 6 (p < 0.001) for both groups, respectively). Ca2+, Mg(2+)-ATPase activity (nmol ATP hydrolyzed/min per milligram protein) in the absence and in the presence of calmodulin increased in the enalapril (6.4 +/- 0.7 to 8.9 +/- 0.95, p < 0.05; 13.4 +/- 1.2 to 17.2 +/- 1.2, p < 0.05, respectively) and captopril (7.0 +/- 0.6 to 8.5 +/- 0.7; 14.4 +/- 1.1 to 16.0 +/- 1.0, p < 0.05, respectively) groups after 6 months of treatment compared within each treated group over time. When patient groups were compared with controls at time 0, 2, 4, and 6 months, the pump activity was higher in the treated groups at 6 months.


CONCLUSIONS
The long-term enhancement of cell membrane Na+, K(+)-and Ca2+, Mg(2+)-ATPase activity associated with enalapril and captopril therapy may represent a specific effect of these agents or alternatively, a nonspecific outcome of blood pressure reduction.
Golik
A
A
Department of Medicine A, Assaf Harofeh Medical Center, Tel Aviv University, Israel.
Weissgarten
J
J
Evans
S
S
Cohen
N
N
Averbukh
Z
Z
Zaidenstein
R
R
Cotariu
D
D
Modai
D
D
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000494:pharmacology / Q000627:therapeutic use; D017301:Ca(2+) Mg(2+)-ATPase / Q000187:drug effects* / Q000378:metabolism; D002216:Captopril / Q000494:pharmacology / Q000627:therapeutic use; D004656:Enalapril / Q000494:pharmacology / Q000627:therapeutic use; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000201:enzymology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000188:drug therapy / Q000201:enzymology*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D000254:Sodium-Potassium-Exchanging ATPase / Q000187:drug effects* / Q000378:metabolism
D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D004656:Enalapril; D002216:Captopril; D017301:Ca(2+) Mg(2+)-ATPase; D000254:Sodium-Potassium-Exchanging ATPase