Catecholamines, Isometric Exercise and Left Ventricular Function

Abstract

The use of plasma noradrenaline as a determinant of sympathetic function has been described by several authors and has resulted from a number of investigations in which acute changes in plasma noradrenaline concentration have been determined in response to a sympathetic challenge (Lake et al., 1976; Osikowska and Sever, 1976). There are, however, major difficulties in the interpretation of isolated values of noradrenaline in plasma because of widespread inter-individual variations in both basal and stimulated levels. Recent studies from Wallin and his co-workers have given encouragement to the validity of plasma noradrenaline as a determinant of sympathetic tone since they claim a positive relationship between sympathetic muscle nerve activity and noradrenaline concentration (Wallin, G., personal communication).