The effect of mental arithmetic in normotensive and hypertensive subjects, and its modification by beta‐adrenergic receptor blockade.

Abstract

I The effects of a 5-min period of sustained mental arithmetic upon blood pressure and heart rate were determined in several groups of healthy subjects and hypertensive patients. 2 The arithmetic produced significant increases in heart rate and blood pressure (both systolic and diastolic) in both normotensive and hypertensive subjects. 3 The blood pressure changes were neither attenuated nor enhanced by the prior administration of ,B-adrenergic receptor blocking drugs (alprenolol, propranolol or metoprolol) on an acute or chronic basis. 4 In subjects habituated to the test the heart rate increase was unaffected by the drugs, but in those less familiar with the test it was usually attenuated.S Although the fi1-adrenoceptor selective blocker, metoprolol, caused decreases in baseline values for blood pressure and heart rate similar to those observed with the use of the two non-selective blockers, it was shown in a double-blind crossover comparison with propranolol that the haemodynamic changes provoked by the mental arithmetic were not less in the presence offi -receptor blockade than when both pf-andfi2-receptors were blocked.6 These findings suggest that, during fi2-adrenoceptor blockade, the haemodynamic effects of minor mental stress are not exaggerated because of uncompensated a-receptor mediated vasoconstriction, such as occurs following adrenaline infusion.

Sympathetic activity is influenced by task difficulty and stress perception during mental challenge in humans.

“…To generalize, mental tasks elicit primarily cardiac output (mostly heart rate)-mediated elevations in arterial pressure (Hejl, 1957) as observed in most subjects in this study. Studies of responses to mental tasks during f8-blockade (Nyberg, Graham & Stokes, 1977;Freyschuss, Hjemdahl, Juhlin-Dannfelt & Linde, 1988) suggest that if one mechanism (e.g. heart rate) for elevating arterial pressure during the task is constrained or eliminated, a different mechanism will compensate so that a given increase in arterial pressure is generated.…”

Cholinergic stimulation with pyridostigmine blunts the cardiac responses to mental stress

“…Emotional or mental stress provokes autonomic adjustments, which in turn cause the typical hemodynamic changes characterized by increased heart rate and blood pressure [1][2][3][4]. Although these effects are part of a normal physiological response, mental stress or emotion may also produce myocardial ischemia [5][6][7], decreased left ventricular ejection fraction [7], and ventricular arrhythmia in patients with coronary artery disease [6,[8][9][10].…”

<i>&beta;</i>-Adrenoceptor-Blocking Agents in the Management of Hypertension

“…Also the rise in pressure in response to mental arithmetic was reduced by propranolol, 320mg/day (Guazzi et al, 1976). However, Nyberg et al (1977) using lower doses of propranolol, or metoprolol, or alprenolol, found that although the peak pressures were reduced in response to mental arithmetic, the rise from baseline was not.…”