title: Effects of different sodium intakes on the antihypertensive and renal effects of single oral doses of nifedipine in hypertensive patients.
abstract: The aim of this study was to investigate whether the antihypertensive and renal effects of Ca2+ antagonists are related to the sodium state of the patients. For this purpose, in a group of 11 patients with essential hypertension we have compared the blood pressure lowering effects of a single oral dose of nifedipine before (100 mmol Na+/day and 40 mmol K+/day) and after sodium depletion (20 mmol Na+/day and 40 mmol K+/day: each period was of 6-8 day duration). During the normal sodium diet nifedipine significantly lowered supine blood pressure (from 185 +/- 13/107 +/- 7 to 161 +/- 13/100 +/- 7 mm Hg, p less than 0.001) and induced a significant rise in Na+ excretion (from 52 +/- 10 to 94 +/- 13 mmol/6 h) and in urine volume (from 520 +/- 80 to 947 +/- 120 ml/6 h; p less than 0.01). Sodium depletion significantly lowered supine blood pressure (152 +/- 12/95 +/- 9 mm Hg, p less than 0.001); nifedipine caused a further and significant blood pressure reduction (142 +/- 11/90 +/- 8 mm Hg, p less than 0.01), but only a minor and not significant increase in sodium excretion (from 10 +/- 2 to 22 +/- 5 mmol/6 h) and urine volume (from 338 +/- 76 to 463 +/- 94 ml/6 h). Our data suggest that the natriuretic action of calcium antagonists is not relevant to their antihypertensive effect.
authors: Istituto di Clinica Medica Generale e Terapia Medica, Università di Milano, Italy.
authors: G
authors: G
authors: Leonetti
authors: L
authors: L
authors: Rupoli
authors: P
authors: P
authors: Sangiorgio
authors: R
authors: R
authors: Gradnik
authors: C
authors: C
authors: Cuspidi
authors: G
authors: G
authors: Bolla
authors: A
authors: A
authors: Zanchetti
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000450:Aldosterone / Q000097:blood; D001794:Blood Pressure; D004039:Diet, Sodium-Restricted; D005665:Furosemide / Q000494:pharmacology; D006339:Heart Rate; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D007668:Kidney / Q000187:drug effects*; D008875:Middle Aged; D009543:Nifedipine / Q000627:therapeutic use*; D012083:Renin / Q000097:blood; D012964:Sodium / Q000652:urine
chemical_list: D000450:Aldosterone; D005665:Furosemide; D012964:Sodium; D012083:Renin; D009543:Nifedipine