An open study was carried out to examine the effect of moclobemide, a new antidepressant reversible inhibitor of MAO-A, on the pressor response induced by oral tyramine added to meals of different lipid and protein composition, and to correlate the blood pressure increase in the tyramine test with that obtained during an exercise test. Eight healthy volunteers of both sexes participated in the study. A tyramine sensitivity and an exercise test were performed beforehand. Subjects were included if, under fasting condition, their systolic blood pressure (SBP) increased by more than 30 mmHg after administration of 400 or 600 mg tyramine. Exercise tests were performed to determine the grade of effort that corresponded to a rise in SBP of 30 mmHg. Subjects received moclobemide 600 mg/d. Starting on Day 7, each subject consumed a standardized meal (52 g lipids, 43 g proteins, 86 g carbohydrates) just before taking moclobemide. Tyramine was added to these meals in daily increasing doses of 50, 100, 150...mg until an increase in SBP > or = 30 mmHg was obtained. On moclobemide treatment, an average dose of 250 mg tyramine (range 150-400 mg) increased SBP by 36.6 mmHg. The time to reach peak SBP was longer (175 min) than in the fasting condition before the trial (40.6 min).(ABSTRACT TRUNCATED AT 250 WORDS)