CATECHOLAMINES, LYMPHOCYTE SUBSETS, AND CYCLIC ADENOSINE-MONOPHOSPHATE PRODUCTION IN MONONUCLEAR-CELLS AND CD4(+) CELLS IN RESPONSE TO SUBMAXIMAL RESISTANCE EXERCISE

We examined the effect of 30 min of submaximal resistance exercise on free and sulphoconjugated plasma catecholamine concentrations determin ed by high performance (-pressure) liquid chromatography separation, t he distribution of circulating lymphocytes quantified by flow cytometr y, and isoproterenol induced cyclic adenosine monophosphate (cAMP) pro duction in mononuclear cells (MNL) and CD4(+) cells. Venous blood samp les were taken before, immediately after and 45 min after exercise. Re sistance exercise increased free plasma adrenaline (A) and noradrenali ne (NA) concentrations, whereas sulphoconjugated catecholamine concent rations remained unchanged. Exercise induced leucocytosis and lymphocy tosis was predominantly manifested by an increase in the number of tot al lymphocytes, monocytes, CD3(+), CD8(+) cells and CD3(-) CD16/CD56() cells. Redistribution resulted in a decrease in the CD4(+): CD8(+) r atio. The total number and distribution of lymphocytes returned to bas eline after 45-min rest. An exercise-induced increase in the number of CD3 - CD16/CD56(+) cells was significantly correlated with the increa se in plasma NA (r = 0.66; P = 0.035), indicating a NA dependent proce ss of redistribution. The cAMP-production in MNL was significantly ele vated after resistance exercise, when cells were stimulated with 1 mu mol . 1(-1) isoproterenol [pre-exercise 16.5 (SD 3.3); postexercise 21 .6 (SD 9.8), 45 min postexercise 10.7 (SD 2.8)]. The cAMP production i n GD4(+) cells was not affected by exercise. Therefore, it is discusse d whether redistribution is responsible for the exercise induced incre ase in cAMP production in MNL.