Effect of hypothermia and delayed thrombolysis in a rat embolic stroke model.
Effect of hypothermia on cerebral infarcts was studied in rats embolized in the right carotid territory. Thirty-four served as normothermic controls receiving saline infusion only. In 16 rats hypothermia of 32 degrees C was induced by cooling with a fan, followed by embolization. The rats were kept hypothermic for the following 3 h before body temperature was raised to 37 degrees C. In 26 rats, treatment with human recombinant tissue plasminogen activator (20 mg/kg i.v. during 45 min), started 2 h after embolization. Finally, 14 rats were treated similarly with hypothermia for 3 h followed by additional rt-PA treatment starting after 2 h. Thrombolytic therapy reduced median infarct volume from 19.5% of affected hemisphere among controls to 4.6% (p = 0.006) in the treated group. Three hours of hypothermia reduced infarct volume to 1.6% (p = 0.0007). Additional rt-PA could not demonstrate further improvement in this experimental setting.
Meden
P
P
Neurovascular Research Laboratory, Rigshospitalet, Copenhagen, Denmark.
Overgaard
K
K
Pedersen
H
H
Boysen
G
G
D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology; D001833:Body Temperature Regulation / Q000502:physiology*; D002341:Carotid Artery Thrombosis / Q000473:pathology / Q000503:physiopathology*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000473:pathology; D002533:Cerebral Angiography; D002536:Cerebral Arteries / Q000473:pathology; D002544:Cerebral Infarction / Q000473:pathology / Q000503:physiopathology; D004195:Disease Models, Animal; D007036:Hypothermia, Induced; D002542:Intracranial Embolism and Thrombosis / Q000473:pathology / Q000503:physiopathology*; D015588:Observer Variation; D051381:Rats; D011994:Recombinant Proteins / Q000494:pharmacology; D015912:Thrombolytic Therapy; D010959:Tissue Plasminogen Activator / Q000494:pharmacology
D011994:Recombinant Proteins; D010959:Tissue Plasminogen Activator