SURGICAL ANTICIPATORY STRESS MANIFESTS ITSELF IN IMMUNOCYTE DESENSITIZATION - EVIDENCE FOR AUTOIMMUNOREGULATORY INVOLVEMENT

The immunocyte behavior (conformational changes and locomotion in resp onse to signal molecule challenge) in patients about to undergo electi ve cardiac surgery was studied to elucidate the effect of psychologica l anticipatory stress on the immune system. Granulocytes and monocytes from 10 patients and 35 non-surgical controls were examined. Computer -assisted microscopic image analysis, capable of measuring cellular co nformational and velocity changes, was used to measure the responsiven ess of these immunocytes to peptidergic and cytokine stimulation. Immu nocyte desensitization would appear to account for the reduction in th eir abilities to respond to chemotaxic challenge associated with the p re-cardiac surgery state, Their abilities to respond to D-Ala2-Met-enk ephalinamide (DAMA) were observed only at much higher concentrations t han previously reported (10-11 M vs, 10-9 M prior to surgery). This fi nding together with the observed decrease in adrenocorticotropin level s compared to nonsurgical controls, suggests that neutral endopeptidas e activity was elevated just prior to surgery, Indeed, neutral endopep tidase activity is statistically elevated in the pre-cardiac surgery s tate. Furthermore, glucocorticoid levels remained constant, within nor mal resting limits, in both groups. Thus, surgical anticipatory stress may manifest itself, in part, as a desensitization of various immunoc ytes. Thus, a psychological anticipatory stress response may be a prec ipitant of the desensitization Although this desensitization seemed no t to involve the entire hypothalamic-pituitary-adrenal axis, the data suggest that psychological anticipatory stress may initially involve a nd influence autoimmunoregulation.