title: The no-reflow phenomenon is a post-mortem artifact.
abstract: Post-ischemic reperfusion impairment, ("no-reflow phenomenon"), was studied in rats subjected to 8-30 minutes of global brain ischemia. During ischemia, rapid and complete loss of cerebral blood flow, EEG and 31P-high energy phosphates (ATP/PCr) was observed. Brain intravascular perfusion defects were examined by injecting carbon black intravenously in a group of rats with stable cardiopulmonary function and in another group subjected to rapid thoracotomy and intraarterial infusion of the carbon marker. Results indicate that global brain ischemic or non-ischemic control rats given intraarterial carbon black after thoracotomy had varying degrees of vessel filling defects in brain resulting in "pale tissue areas" suggestive of impaired perfusion (no-reflow). All rats given carbon black intravenously whether global brain ischemic or not, showed normal cerebrovascular filling of the carbon black and absence of "pale tissue areas". In addition, post-ischemic cerebral reperfusion following 8-30 minutes global brain ischemia can reverse neuroelectric, energy metabolite and cerebral blood flow loss in rats whose cardiopulmonary function is not compromised. These findings indicate that the "no-reflow phenomenon" is an agonal or post-mortem artifact observed in the presence of cardiopulmonary failure.
authors.affiliation: Division of Neurosurgery, University of Ottawa, Faculty of Medicine, Ontario, Canada.
authors.forename: J C
authors.initials: JC
authors.lastname: de la Torre
authors.forename: T
authors.initials: T
authors.lastname: Fortin
authors.forename: J K
authors.initials: JK
authors.lastname: Saunders
authors.forename: K
authors.initials: K
authors.lastname: Butler
authors.forename: M T
authors.initials: MT
authors.lastname: Richard
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D016477:Artifacts; D001921:Brain / Q000473:pathology*; D001925:Brain Damage, Chronic / Q000473:pathology*; D002545:Brain Ischemia / Q000473:pathology*; D002536:Cerebral Arteries / Q000473:pathology; D002540:Cerebral Cortex / Q000098:blood supply / Q000473:pathology; D002560:Cerebrovascular Circulation / Q000502:physiology; D008297:Male; D010725:Phosphocreatine / Q000378:metabolism; D011180:Postmortem Changes; D051381:Rats; D011919:Rats, Inbred Strains; D015427:Reperfusion Injury / Q000473:pathology*
chemical_list: D010725:Phosphocreatine; D000255:Adenosine Triphosphate