Attenuation by indomethacin of the antihypertensive effects of enalapril may be independent of sodium retention [Atenuacao dos efeitos anti-hipertensores do enalapril pela indometacina. Sua independencia da retencao renal de sodio]

• Type: Article in International Scientific Journal
• Date: 1996

Authors

Polonia, J (Author) FMUP; Gama, G (Author) Other; Santos, A (Author) FCNAUP

Journal

Title: Revista Portuguesa de Cardiologia

Vol. 15 No. 6

Pages: 485-492+460

ISSN: 0870-2551

Publisher: Sociedade Portuguesa De Cardiologia

Indexing

ISI Web of Knowledge

Scopus - 3 Citations

Other information

Authenticus ID: P-007-720

Abstract (EN): Objective: To evaluate in hypertensive patients whether or not the sodium-retaining effects of indomethacin can explain the indomethacin-induced attenuation of enalapril antihypertensive effects. Design: Randomized, singleblinded, placebo controlled study with a placebo phase (2 weeks) followed by enalapril 20 mg/d (4 weeks, once daily) and enalapril 20 mg + indomethacin 75 mg/d (1 week). Enalapril dose increased up to 40 mg/d if inadequate response to 20 mg. Patients: Twenty-four patients with mild-moderated hypertension, showing an adequated response to enalapril (20-40 mg/d). Methods: Blood pressure evaluated by 'casual' methods and by 24-hour ambulatory blood pressure monitoring, measurement of 24-hour urinary sodium excretion and fractional excretion of sodium: at the end of placebo, enalapril and enanalpril + indomethacin treatments. Determination of the correlations between the changes induced by indomethacin (when added to enalapril) on the blood pressure and on sodium excretion effects of enalapril. Results: Enalapril significantly reduced casual blood pressure (systolic/diastolic) by 33/18 mmHg and 24-hour blood pressure by 20/9 mmHg. When added to enalapril, indomethacin attenuated (by 50%) the antihypertensive effects of enalapril and significantly decreased the 24-hour (from 120 ± 11 mmol to 106 ± 10 mmol) and fractional excretion of sodium (from 1.11 ± 0.09% to 0.75 ± 0.06%). However, the indomethacin-induced attenuation of enalapril hypotensive effects did not correlate with indomethacin-induced changes of sodium excretion. Conclusions: When indomethacin is administrated to hypertensive patients that are well controlled with enalapril, it produces a marked attenuation of enalapril hypotensive effects and procudes sodium retention. However, the amount of the attenuation of the hypotensive effects of enalapril by indomethacin are completely independent of the amount of the indomethacin-induced sodium retention. These results suggest that the mechanisms involved in interaction between both drugs at the blood pressure domain are probably localized at an extra-renal level.

Language: Portuguese

Type (Professor's evaluation): Scientific

No. of pages: 8