Secretory immunoglobulin A and cardiovascular responses to acute psychological challenge.

Cardiovascular activity and secretory immunoglobulin A (sIgA) in saliva were recorded at rest, during a 30-min computer game task, and during subsequent recovery. Blood pressure (BP) rose and remained elevated during the task and returned to resting levels during recovery. This pressor response was produced by increased total peripheral resistance rather than increased cardiac output. SIgA secretion rate also increased during the task, although the effect proved significant only toward the end of the task. As such, the data provide preliminary indication that sIgA is sensitive to acute psychological challenge in the laboratory. Although correlational analyses revealed that sIgA reactions were stable, they were not significantly correlated with pressor reactions. The influence of task uncertainty was explored by comparing individuals who had previously played the computer game with those who had not. Task-induced increases in BP and sIgA were a feature of individuals new to the computer game. In contrast to these novice players, experienced players showed minimal increases in BP and no increases in sIgA.