Secretory immunoglobulin A and cardiovascular reactions to mental arithmetic, cold pressor, and exercise: Effects of beta-adrenergic blockade

We investigated the influence of sympathetic nervous system processes on mu cosal immunity by comparing the effects of beta-adrenoceptor blockade with 40 mg propranolol and placebo on secretory immunoglobulin A (sIgA) at rest and during paced serial arithmetic, cold presser, and submaximal cycling. T hese tasks produced patterns of cardiovascular activity indicative of combi ned alpha- and beta-adrenegic, alpha-adrenergic, and beta-adrenergic activa tion, respectively. The effectiveness of the beta blockade was confirmed by the attenuation under propranolol of the shortening of the cardiac preejec tion period and the tachycardia elicited by mental arithmetic and exercise. The cold presser test did not affect sIgA under either the placebo or the propranolol. Mental arithmetic increased sIgA concentration, and this incre ase was not blocked by propranolol. Exercise elicited increases in both sIg A concentration and sIgA secretion rate, which were not diminished by beta blockade. These data suggest that sIgA is not regulated by beta-adrenergic mechanisms.