Antihypertensive and renal effects of nicardipine.

Abstract

Both the acute blood pressure lowering and renal effects of the calcium antagonist nicardipine and those after 1 week's treatment were investigated in 10 normotensive volunteers and in 10 patients with mild to moderate essential hypertension. 2 After 1 week of placebo, nicardipine was administered orally for 1 week (20 mg three times daily), Investigations, done on the first and last day of nicardipine treatment were compared with those on the last day of placebo. 3 During water loading, nicardipine increased urinary volume and urinary excretion of sodium significantly after 1 week nicardipine treatment. 4 In the normotensive group the natriuretic effect was caused by a decrease of fractional proximal and distal reabsorption of sodium. In the hypertensive group the natriuresis was achieved mainly by an increase of the rate of glomerular filtration (GFR) and also by a slight distal effect. 5 Our results show that nicardipine had natriuretic effects. There were trends suggesting that the renal effects may differ between patients with essential hypertension and normotensive volunteers, but the findings might also be related to differences in age between the groups.

Multiple effects of calcium entry blockers on renal function in hypertension.

“…Other studies revealed that short-term treatment with diltiazem 62 or nifedipine 66 or administration of nicardipine 67 for 1 week produced a reduction of blood pressure in hypertensive subjects comparable to that induced by identical doses in normotensive subjects (see Table 3). However, the increases in RBF, 6667 GFR, 66 and U N , were greater in hypertensive than in normotensive subjects.…”

“…These findings could have important clinical implications. In fact, an exaggerated increase in intrarenal resistance found in approximate- 62 Leonetti et al 63 Leonetti et al 65 Yokoyama and Kaburagi 66 Van Schaik et al 67 Normotension Leonetti et al 63 Leonetti et aJ. H …”

“…6 Hence, the renal effects of a drug should be established first by direct infusion into the renal artery at constant renal perfusion pressure; subsequently, it should be determined how these local effects are modified when systemic pressure is allowed to change. 67 Furthermore, the administration of a drug into the renal artery will allow determination of whether the natriuretic effect is produced by direct tubular action or whether it is the result of renal vasodilatation. In the first instance, the increase of U N , shifts the natriuresis curve to the left without changing RBF or GFR; in the second instance, the increase in U N , is accompanied by a proportional elevation of RBF and GFR.…”

The Intrarenal Renin-Angiotensin System: From Physiology to the Pathobiology of Hypertension and Kidney Disease

“…Short-term administration of nifedipine to normotensive subjects or hypertensive patients produced a significant increase in plasma renin activity (Aoki et al, 1976;Pedersen et al, 1979;Hiramatsu et al, 1982;Kusano et al, 1982;Leonetti et al, 1982;Kiowski et al, 1983). Results for plasma RAS components were inconsistent after treatment with nitrendipine (Thananopavarn et al, 1984;Luft et al, 1985;Pedrinelli et al, 1986), nicardipine (van Schaik et al, 1984;Elliott et al, 1985), amlodipine (Krenek et al, 2004;Lamarre-Cliche et al, 2005), or verapamil (Muiesan et al, 1982;Guthrie et al, 1983;Frohlich, 1985). Some calcium blockers such as azelnidipine may suppress the RAS although its mechanism remains unclear (Oizumi et al, 1989).…”

Diuretic and natriuretic effects of nifedipine in healthy persons.

“…More recently this diuretic and natriuretic capacity has been confirmed for a number of related calcium antagonists e.g. nifedipine (Ene et al, 1985), nitrendipine (Ene etal., 1985;Wallia etal., 1985), nicardipine (van Schaik et al, 1984), and felodipine (Sluiter et al, 1985). As reviewed elsewhere, several mechanisms could account for this natriuretic effect, and the tubular site of action is still debated (Zanchetti & Leonetti, 1985).…”