A RESEARCH TRAIL OVER HALF A CENTURY

The author describes his major research activities from the time of hi s PhD thesis work (1937-1940) on properties of erythrocyte membranes t o the present. His involvement in research on circulatory shock during World War II: led to a continuing interest in the physiology and phar macology of smooth muscle and cardiac muscle. From 1956 to 1978, his m ain areas of research were photorelaxation of blood vessels, factors i nfluencing contractility of cardiac muscle, peripheral adrenergic mech anisms, and receptor theory. The major findings of his and his collabo rators in these areas are described. He then recounts how an accidenta l finding in an experiment in 1978 on preparations of rabbit aorta eve ntually led to the discovery of endothelium dependent relaxation and t he endothelium-derived relaxing factor (EDRF); and how additional find ings led him to propose in 1986 that EDRF is nitric oxide.