Showing papers by "Pierre Larochelle published in 1991"

Effect of a novel monoamine-oxidase inhibitor, moclobemide on the sensitivity to intravenous tyramine and norepinephrine in humans.

Abstract: This study compared the effects of moclobemide (Ro11-1163), a selective and reversible inhibitor of monoamine-oxidase (MAOI) type A and phenelzine, an irreversible non-selective MAOI, on the pressor responses to IV tyramine and norepinephrine. Because of the reversibility of this inhibition, the pressor effect of tyramine was expected to be minimal. Twelve healthy men participated in this randomized double-blind, placebo-controlled, crossover study. Volunteers began with oral treatment of moclobemide (100 mg TID) or phenelzine (15 mg TID) for 1 week followed by placebo treatment for 2 weeks and then moclobemide or phenelzine treatment for another week. The tyramine and norepinephrine challenge tests were conducted at baseline and then at weekly intervals, for a total of five challenges. The average tyramine dose that was required to increase systolic blood pressure by 25 mm Hg (PD25) was 1.6 +/- 0.2 mg after moclobemide treatment, which was lower (P less than .01) than the baseline value of 3.6 +/- 0.7 mg and that after phenelzine (3.0 +/- 0.5 mg) treatment. Moclobemide did not influence norepinephrine sensitivity. In conclusion, moclobemide mildly decreased the sensitivity to IV tyramine as compared with placebo and phenelzine.

A Double-Blind Study Comparing Enalapril and Hydrochlorothiazide as Single Agents in the First-Line Therapy of Mild to Moderate Essential Hypertension

Abstract: Enalapril administered once daily as a single agent (10 to 40mg) was compared with hydrochlorothiazide (25 to 100mg) in a double-blind randomised multicentre study in 193 patients with untreated sitting diastolic blood pressure of 95 to 114mm Hg. A total of 95 patients (51 male/44 female, mean age 52.2 years) received enalapril and 98 patients (66 male/32 female, mean age 51.3 years) received hydrochlorothiazide. After a 4-week placebo washout, patients received either enalapril 10mg or hydrochlorothiazide 25mg. Blood pressure was measured in the morning, and the dosage was titrated at 2-week intervals until the optimal diastolic pressure of ⩽90 mmHg was achieved or maximum dosage was reached (enalapril 40mg or hydrochlorothiazide 100mg). The patient was maintained on that dose for a further 6 weeks. On completion of therapy, the mean blood pressure in the enalapril group was 140.9/88.6mm Hg, representing a mean decrease from baseline of 13.6/11.5mm Hg. In the hydrochlorothiazide group, mean blood pressure at the end of therapy was 142.8/90.0mm Hg, representing a mean decrease of 14.9/10.7mm Hg. 70.8% of patients on enalapril (63/89) achieved optimal diastolic blood pressure, while 61.1% of those on hydrochlorothiazide (55/90) achieved optimal diastolic blood pressure between treatments. Nine patients withdrew because of adverse effects, 3 on enalapril and 6 on hydrochlorothiazide. Changes in clinical laboratory values during therapy were more frequent in the hydrochlorothiazide group (p < 0.05) and were highly significant for serum potassium (p < 0.001). ECG abnormalities (flat or negative T wave) were observed more frequently (p < 0.01) in the hydrochlorothiazide group. The results of this study indicate that enalapril administered once daily as a single agent is as effective and as well tolerated as hydrochlorothiazide in the initial treatment of mild to moderate hypertension.