Immune cell CD62L and CD11a expression in response to a psychological stressor in human hypertension

This study examined the effects of hypertension and an acute psychological stressor on white blood cells and their expression of CD62L and CD11a. Seventeen mild hypertensive and 23 normotensive volunteers were studied prior to and following a standardized laboratory public speech. In response to the speech, all subjects increased the number of circulating leukocyte populations (p's<.01). Patients with hypertension increased the number of circulating white blood cells more than normotensives (p<.01). Hypertensives also showed a greater increase in the number of circulating CD3(+)CD8(+) T cells (p<.02) in response to the speech. Only hypertensives increased the number of circulating CD8(+)CD62L(high) T cells (p=.001). The density of CD11a on lymphocytes was increased in all subjects following the speech (p<.001). Hypertensives showed a greater mean density of CD11a on lymphocytes (p<.01). Coupled with observations of increased expression of the endothelial CD11a ligand ICAM-1 in hypertension, these findings are consistent with the notion that patients with hypertension exhibit a circulatory environment conducive to increased leukocyte adhesion. Exposure to repeated psychological stressors may further augment this potentially adverse circulatory environment.