Beta-adrenergic regulation of the blood lymphocyte phenotype distribution in normal subjects and splenectomized...

The beta-adrenergic effect on the release of immunoregulatory cells from the spleen was investigated by physical stress testing (bicycle ergometry up to submaximal work capacity) in 19 normal subjects (15 males, median 21 years) and in 10 male patients splenectomized for trauma (median 29 years). It was repeated in 6 subjects of each group during beta-blockade with 80 mg oxprenolol. Blood samples for leucocyte analysis were taken before and at the end of the test. Leucocyte subpopulations were analyzed in a cytofluorograph after staining of buffy coat cells by direct (B cells) or indirect immunofluorescence with monoclonal antibodies directed against the phenotypes of T- (Leu-1), T helper- (Leu-3a), T suppressor/cytotoxic (Leu-2a) cells and natural killer (OKM1+ lymphocytes) cells. In the controls all leucocyte subsets increased at ergometry, but B-, Leu-2a- and OKM1-cells increased more than Leu-3a cells. During beta-blockade the leucocyte changes reached only 50% of the value without treatment; the B- and Leu-2a cell mobilization was reduced more than the Leu-3a-, OKM1 cell- and monocyte changes. In splenectomized patients the proportional cellular changes were only half of those found in normal subjects, except for the Leu-3a cells which were not released. Beta-blockade during ergometry had no effect on Leu-3a cells, a similar effect on B- and Leu-2a cells as in normal subjects and a stronger effect on granulocytes, monocytes and OKM1 cells than in controls. In conclusion, the B- and Leu-2a cell mobilization from the spleen (50%) was beta-adrenoceptor dependent, while the one from other lymphoid organs was beta-adrenoceptor independent. The strongly spleen dependent Leu-3a cell changes were not beta-adrenoceptor mediated. Granulocyte-, monocyte- and OKM1 cell changes were only partly spleen dependent. The spleen independent changes however were strongly beta-adrenoceptor dependent.