Abstract: | Experiments were carried out on dogs with the internal carotid artery circulatory isolated and continuously perfused in situ with oxygenated Ringer-Krebs bicarbonate solution. Prostaglandins A1 and B1 (PG-A1 and PG-B1) exerted a constrictory effect on the artery. The effect of both prostaglandins was significantly less, but more prolonged than that of the same doses of serotonin. A possible role of PG-A1 and PG-B1 in the development of vasospasm is testified to by the following experimental results: a) during repeated action of PG-A1 AND PG-B1 their effect did not change, and therefore it should not decrease under prolonged influence of these prostaglandins on the vascular wall;) b) the mentioned prostaglandins caused potentiation of the constrictory effect of both serotonin and norepinephrine. |