Erythrocyte sodium cannot predict hypotensive effects of calcium channel blockers.
Antihypertensive efficacy of the calcium channel blocker, nilvadipine, was investigated in 21 patients with essential hypertension in relation to the intracellular sodium concentration ([Na]i) in erythrocytes and clinical variables, such as age, body weight, pretreatment blood pressure and plasma renin activity. Dihydropyridine nilvadipine reduced mean blood pressure from 120 +/- 6 to 106 +/- 8 mmHg (p < 0.01). The hypotensive effect of nilvadipine was positively correlated with age (r = 0.67, p < 0.01) and inversely correlated with plasma renin activity (r = -0.62, p < 0.01), but was not correlated with erythrocyte [Na]i or any other indices. Erythrocyte [Na]i was decreased with nilvadipine treatment (8.27 +/- 1.69 to 7.97 +/- 1.49 mM, p < 0.01). However, no link was found between the change in [Na]i and the hypotensive effect of the drug. In conclusion, the antihypertensive efficacy of nilvadipine was predictable by age and renin status, but not by erythrocyte [Na]i. A significant role of reduction of [Na]i in the hypotensive effect of the calcium channel blockers was not detected.
Oshima
T
T
Department of Clinical Laboratory Medicine, Hiroshima University School of Medicine, Japan.
Matsuura
H
H
Ozono
R
R
Ishida-Kainouchi
M
M
Ishida
T
T
Ishibashi
K
K
Watanabe
M
M
Okura
Y
Y
Kanbe
M
M
Kajiyama
G
G
D000367:Age Factors; D000959:Antihypertensive Agents / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004912:Erythrocytes / Q000737:chemistry*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000031:analogs & derivatives / Q000494:pharmacology; D012083:Renin / Q000097:blood; D012964:Sodium / Q000097:blood*
D000959:Antihypertensive Agents; D002121:Calcium Channel Blockers; C035100:nilvadipine; D012964:Sodium; D012083:Renin; D009543:Nifedipine