The action of metaraminol (Aramine) on myocardial contractility

Abstract

Metaraminol [levo-l-(m-hydroxy-phenyl)-2-amino-l-propanol] - a potent weapon in combating myocardial shock - can be administered intra-venously, intra-muscularly or subcutaneously and is therefore of great importance in daily practice. Reports (SARNOFF et al., 1954; LINSAY et al., 1954; MORGAN et al., 1957; STECKEL, 1956; WEIL and SPINK, 1955; BESTERMAN, 1959) suggest that besides a peripheral vaso-constrictive action metaraminol also has a stimulating effect on ventricular function. Metaraminol causes a rise in mean blood-pressure and increases the heart rate. Since these factors may be responsible for the improvement of cardiac function (KRUTA, 1937; MEIJLER, et al., 1961, 1962), a direct effect on the myocardium has not been proved. To demonstrate a possibly direct effect of metaraminol on myocardial contractility it is necessary to design a set-up which allows this effect to be studied at a constant coronary perfusion-pressure and a constant heart rate.