The "no-reflow" phenomenon in cerebral circulation.
BACKGROUND
The purpose of our research was to study the pattern of post-ischemic cerebral hemodynamic changes and observe the impact of enalapril on the course of these changes in cats.


METHODS
The experiments were carried out on anesthetized cats using the autohemoperfusion method in cerebral and peripheral vessels with a stable volume of blood. Transitional peripheral (lower limb) and brain ischemia was simulated by stopping the autohemoperfusion pump for 15 minutes, tying various anastomoses in the neck region, and reducing arterial blood pressure (ABP) to 40-30 mm Hg, followed by reinfusion of the shed blood.


RESULTS
Intravenous administration of enalapril solution in a dosage of 0.25 mg kg-1 in the early phase of reperfusion (10 minutes into the postischaemic period) prevented the development of long-term "no-reflow"of cerebral blood flow, as observed in the controls. There was a 40.8+/-3.2% reduction of cerebrovascular tone, 39.3+/-3.1% in peripheral vessels, and 44.7+/-1.5% lower arterial blood pressure at the end of 120 minutes.


CONCLUSIONS
Enalapril caused a reduction of cerebrovascular tone, completely eliminating the "no-reflow" syndrome after brain ischemia and somewhat potentiated the hyperperfusion phase. At the same time, the drug did not aggravate the general hypotension observed after ischemia in the controls.
Department of Pharmacology, University of Ghana Medical School, PO Box 4236, Accra, Ghana. asiedugyekye@yahoo.co.uk
Isaac Julius
IJ
Asiedu-Gyekye
Akadii
A
Vaktorovich
D000818:Animals; D001163:Arteriovenous Anastomosis; D001921:Brain / Q000473:pathology; D002545:Brain Ischemia; D002415:Cats; D002560:Cerebrovascular Circulation; D004656:Enalapril / Q000494:pharmacology; D005121:Extremities / Q000473:pathology; D007511:Ischemia
D004656:Enalapril