Å. Wennmalm

Effect of prostaglandin synthesis inhibitors on basal and CO2-stimulated cerebral blood flow in man

Abstract The present data do not provide evidence that basal or CO 2 -stimulated human cerebral blood flow is under control of locally formed PG. It is suggested that the CBF decreasing effect elicited by indomethacin is separated from its inhibitory effect on PG formation.

Effect of prostanoids on the coronary circulation

After the discovery of prostacyclin (PGI2) (Moncada et al., 1976) the pronounced biological actions of this compound led to a number of different hypotheses concerning its role in various physiological and pathophysiological states. Due to its continuous formation in the vascular endothelium throughout the systemic and pulmonary circulatory systems the platelet anti-aggregatory effect of PGI2 was considered to balance the pro-aggregatory effect of thromboxane A2 (TxA2) (Gryglewski et al., 1976). The vasodilator action of PGI2 was also considered to be of significance in the local regulation of blood flow in various tissues, especially in the coronary circulation. The expectations on an important role of PGI2 in coronary physiology were based not only on the coronary relaxant effect of the compound observed in studies on isolated coronary vessels from various species, including man, but also on studies on inhibition of prostaglandin (PG) formation in various animal in vivo models.