No-reflow phenomenon in the cerebral circulation of the gerbil.

The no-reflow phenomenon has been produced in the cerebral hemispheres of the gerbil by 30 minutes of bilateral carotid artery occlusion. The no-reflow phenomenon was found to develop in relation to the fall in blood pressure which occurred on release of bilateral carotid clips. Metaraminol tartrate intravenously prevented the fall of blood pressure and significantly reduced the occurrence of the no-reflow phenomenon. Metaraminol tartrate, however, did not alter the morbidity or mortality of carotid artery occlusion for 30 minutes. There is thus no support from these experiments for the view that the no-relow phenomenon plays an important functional role in the reversibility of the effects of severe cerebral ischaemia.