The effect of adrenaline, insulin and hydrocortisone on human peripheral blood lymphocytes studied by cell surface markers.

Changes in numbers of peripheral blood lymphocytes from healthy individuals were calculated from samples collected before and after parenteral administration of adrenaline, insulin and hydrocortisone, respectively. A marked increase in circulating lymphocytes was noted in response to adrenaline and insulin. However, subpopulation analysis showed a decrease in the proportion of T-lymphocytes, estimated as cells forming rosettes with sheep red blood cells after incubation in the cold and a corresponding increase in proportion of lymphocytes having receptors for C3 (non-T lymphocytes). In contrast, lymphocyte numbers were unaffected by hydrocortisone. The results indicate that a decreased proportion of circulating T-lymphocytes and an increase of non-T-lymphocytes may be the result of adaptive changes in response to various forms of stress and hence is to be expected in several clinical conditions.