Physiological and pathophysiological aspects of cardiac prostaglandins

It has now been demonstrated that prostaglandins produce a wide variety of actions on cardiac tissue. These effects are quite complex and are dependent on such factors as type of prostaglandin, animal species, experimental format, as well as the amount of prostaglandin employed. The last factor is of particular concern since the administration of large amounts of prostaglandins may not truly reflect the actual actions of the endogenously synthesized prostaglandins which are likely to be at a very low concentration. In this review we have attempted to analyze the pharmacological properties of prostaglandins on cardiac tissue including coronary arteries and myocardium as well as the subcellular basis for their actions. The possible reasons for the diverse effects of prostaglandins under different experimental conditions have been pointed out. An effort has also been made to synthesize the existing information concerning the actions of prostaglandins on heart in terms of current concepts. A discussion is presented concerning the role of endogenously synthesized prostaglandins in physiological and pathological aspects of cardiac performance and the potential use of prostaglandins and prostaglandin synthesis inhibitors in the treatment of heart disease.