Renal response to the angiotensin II receptor subtype 1 antagonist irbesartan versus enalapril in hypertensive patients.
OBJECTIVE
To compare the acute and sustained renal hemodynamic effects on hypertensive patients of 100 mg irbesartan and 20 mg enalapril each once daily.


METHODS
Twenty patients (aged 35-70 years) with uncomplicated, mild-to-moderate essential hypertension and normal serum creatinine levels completed this study.


METHODS
After random allocation to treatment (n=10 per group), administration schedule (morning or evening) was determined by further random allocation, with crossover of schedules after 6 weeks' therapy. Treatment and administration assignments were double-blind. Twenty-four-hour ambulatory blood pressure was monitored before and after 6 and 12 weeks of therapy. Renal hemodynamics were determined on the first day of drug administration and 12 and 24 h after the last dose during chronic treatment.


RESULTS
Administration of each antihypertensive agent induced a renal vasodilatation with no significant change in glomerular filtration rate. However, the time course appeared to differ: irbesartan had no significant acute effect 4 h after the first dose, but during chronic administration a renal vasodilatory response was found 12 and 24 h after the dose; enalapril was effective acutely and 12 h after administration, but no residual effect was found 24 h after the dose. Both antihypertensive agents lowered mean ambulatory blood pressure effectively, with no significant difference between treatments or between administration schedules (morning versus evening).


CONCLUSIONS
Irbesartan and enalapril have comparable effects on blood pressure and renal hemodynamics in hypertensive patients with normal renal functioning. However, the time profiles of the renal effects appear to differ, which might be important for long-term renoprotective effects.
Pechère-Bertschi
A
A
Department of Medicine, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
Nussberger
J
J
Decosterd
L
L
Armagnac
C
C
Sissmann
J
J
Bouroudian
M
M
Brunner
H R
HR
Burnier
M
M
D000328:Adult; D000368:Aged; D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001713:Biphenyl Compounds / Q000008:administration & dosage / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004656:Enalapril / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology*; D000077405:Irbesartan; D008297:Male; D008875:Middle Aged; D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2; D012079:Renal Circulation / Q000187:drug effects*; D012084:Renin-Angiotensin System / Q000187:drug effects; D013777:Tetrazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D013997:Time Factors; D014664:Vasodilation / Q000187:drug effects
D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D001713:Biphenyl Compounds; D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2; D013777:Tetrazoles; D004656:Enalapril; D000077405:Irbesartan