PLASMA-CATECHOLAMINES, BETA-ADRENERGIC RECEPTORS, AND ISOPROTERENOL SENSITIVITY IN ENDURANCE TRAINED AND NON-ENDURANCE TRAINED VOLUNTEERS
PLASMA-CATECHOLAMINES, BETA-ADRENERGIC RECEPTORS, AND ISOPROTERENOL SENSITIVITY IN ENDURANCE TRAINED AND NON-ENDURANCE TRAINED VOLUNTEERS
复制标题
DOI：
10.1007/bf00943364
复制
发表时间：
1984-01-01
影响因子：
3
通讯作者：
KEUL, J
中科院分区：
文献类型：
--
作者：
LEHMANN, M;DICKHUTH, HH;KEUL, J
Please try later.
Six male non-endurance trained subjects (S) and 6 marathon runners (M) underwent graded treadmill exercise (T) and isoproterenol stimulation (I; 2 and 4 .mu.g .cntdot. min-1). .beta.-Adrenergic receptor density was additionally determined as the amount of 3H-Dihydroalprenolol (DHA) specifically bound on intact polymorphonuclear leukocytes. Heart rate, VO2 uptake, lactate, plasma noradrenaline [norepinephrine], and adrenaline [epinephrine] were estimated during T. Heart rate, stroke volume, cardiac output, as well as lactate, glucose, free fatty acids (FFA), and glycerol levels in the blood were determined during I. M showed the known training-dependent responses during T, such as lower heart rates, lactate levels, and plasma catecholamines at identical work loads, as well as higher VO2 max than S. I-induced cardiac output increase was quite similar in both groups. Stroke volume increased significantly in M and stayed constant in S. Lactate decreased (S), glucose increased significantly (M), glycerol increased similarly in both groups, FFA rise was less marked in S. I-induced stroke volume response (I) may be indicative of a more economic regulation of heart work in M than S. Lactate decrease and less marked FFA increase, as observed in S, may be the result of a somewhat higher cardiac energy demand, dependent on less economic heart work. Higher DHA-binding as observed in M, as well as stroke volume response and glucose increase, may be indicators of a training-dependent rise in sensitivity to catecholamines. The unsolved question is to what extent .beta.-receptor responses in intact blood cells are significant for receptor behavior in other organs.