Effects of Prostaglandins E1, E2, A1, A2 and F2 alpha on the Canine Carotid Arterial Blood Flow, Cerebrospinal Fluid Pressure and Intraocular Pressure.
OKLAHOMA UNIV HEALTH SCIENCES CENTER OKLAHOMA CITY
Pagination or Media Count:
The effects of the intraarterial i,a or intravenous i.v. injection or prostaglandins E1PGE1, E2 PGE2, A1 PGA1, A2 PGA2 and F2 alpha PGF2 alpha on the carotid circulation, intraocular pressure IOP and cerebrospinal fluid pressure CSFP were studied in anesthetized dogs. The i.a. injection PGE1, PGE2 or PGA2 into the carotid artery directly decreases the carotid vascular resistance whereas that of PGF2 alpha directly increased it. The i.v. injection of PGE1, PGE2, and PGA2 increases heart rate, carotid arterial blood flow, IOP and CSFP as systemic arterial pressure decreases. On the other hand, the i.v. injection PGF2 alpha decreases heart rate, carotid arterial blood flow and CSFP. Both systemic arterial pressure and IOP increase during a single i.v. infusion and decrease during a continuous i.v. infusion of PGF2 alpha. This suggests that the changes in IOP and CSFP by the PGs are due not only to their direct effect but also to their effect on carotid arterial blood flow. During a continuous i.v. infusion of PGE1, PGE2, or PGA2, carotid arterial blood flow gradually decreases toward control values after its initial, marked increase. It is concluded that a single i.a. or i.v. injection or a short i.v. 10 min infusion of PGE1 or PGE2 may be more effective than a prolonged continuous i.v. infusion of PGE1 or PGE2 for alleviating the cerebral vascular spasm in patients. Modified author abstract