Cholinergic stimulation with pyridostigmine blunts the cardiac responses to mental stress.
Mental stress may induce myocardial ischemia and ventricular arrhythmia in patients with coronary artery disease, and cholinergic stimulation is a potential protective mechanism. The purpose of this study was to determine the effect of pyridostigmine bromide (PYR), a reversible cholinesterase inhibitor, on the cardiac responses to a mental stress challenge. Twelve healthy young volunteers were submitted to a mental stress test (arithmetic test) 2 hours after the oral administration of either placebo or PYR (45 mg) on two separate days, following a randomized crossover double-blind protocol. Heart rate was reduced after both placebo and PYR (p < 0.05), but the cardiac responses to the mental stress were lower with PYR (p < 0.05): mean RR interval (mean +/- SE)-placebo: 730 +/- 19 msec; PYR: 769 +/- 21 msec; Peak systolic pressure-placebo: 129 +/- 4 mmHg; PYR: 124 +/- 3 mmHg; Peak diastolic pressure-placebo: 92 +/- 3 mmHg; PYR: 89 +/- 4 mmHg; Mean rate-pressure product-placebo: 10,496 +/- 412 bpm x mmHg; PYR: 9,746 +/- 383 bpm x mmHg. In conclusion, 45 mg of pyridostigmine blunted the pressor and chronotropic responses to mental stress in healthy young subjects.
Nóbrega
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Department of Physiology, Universidade Federal Fluminense, Niterói, RJ, Brazil. anobrega@web4u.com.br
Carvalho
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Santos
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Soares
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D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D018679:Cholinergic Agonists / Q000494:pharmacology*; D002802:Cholinesterases / Q000097:blood; D005260:Female; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D011729:Pyridostigmine Bromide / Q000494:pharmacology*; D013315:Stress, Psychological / Q000503:physiopathology*; D013997:Time Factors
D018679:Cholinergic Agonists; D002802:Cholinesterases; D011729:Pyridostigmine Bromide