RELATION BETWEEN BETA-ADRENERGIC-RECEPTOR DENSITY AND LYMPHOCYTE-PROLIFERATION ASSOCIATED WITH ACUTE STRESS

The relations between acute changes in beta-adrenoreceptor density on lymphocytes and lymphocyte proliferation to a laboratory speech stress or were examined. Male participants either prepared and delivered a ch allenging speech task or read from a list of words. Participants engag ed in the speech task, but not those involved in reading, exhibited si gnificant increases in systolic blood pressure (an index of sympatheti c nervous system arousal) and beta-adrenoreceptor density, accompanied by significant decreases in lymphocyte proliferation to pokeweed mito gen (PWM) but not concanavalin A (Con A). Increases in beta-adrenorece ptor density significantly predicted decreases in lymphocyte activity in response to both mitogens. The increases in beta-adrenoreceptor den sity in the speech task condition occurred within 5 min after the base line period, when participants were preparing for the speech task, but not yet speaking. These findings suggest that an acute stressor elici ting sympathetic nervous system activity can evoke rapid changes in be ta-adrenoreceptor activity and decreases in mitogenic responses.