Duration of stressor and natural killer cell activity

Abstract To examine whether duration of an acute stressor affected the time line of natural killer cell (NK) activity in response to acute stress, this study collected NK measures from 31 males and 24 females at six times (before, during and after either a 5-min or M-min computerized Stroop task). Both stress periods were associated with increased self-report of distress and anxiety, and participants in the 30-min task group had increased systolic and diastolic blood pressures and heart rate. Regardless of task length, NK activity was elevated during all in-task samples, and activity returned to baseline levels following the task, where it remained through the duration of the study. However, computation of NK activity per cell in a subset of subjects suggested that increases in activity were due to a redistribution of NK cells to the periphery. No gender differences in NK cell reactivity were found.