A novel method for inducing focal ischemia in vitro.
Current in vitro models of stroke involve applying oxygen-glucose deprived (OGD) media over an entire brain slice or plate of cultured neurons. Thus, these models fail to mimic the focal nature of stroke as observed clinically and with in vivo rodent models of stroke. Our aim was to develop a novel in vitro brain slice model of stroke that would mimic focal ischemia and thus allow for the investigation of events occurring in the penumbra. This was accomplished by focally applying OGD medium to a small portion of a brain slice while bathing the remainder of the slice with normal oxygenated media. This technique produced a focal infarct on the brain slice that increased as a function of time. Electrophysiological recordings made within the flow of the OGD solution ("core") revealed that neurons rapidly depolarized (anoxic depolarization; AD) in a manner similar to that observed in other stroke models. Edaravone, a known neuroprotectant, significantly delayed this onset of AD. Electrophysiological recordings made outside the flow of the OGD solution ("penumbra") revealed that neurons within this region progressively depolarized throughout the 75 min of OGD application. Edaravone attenuated this depolarization and doubled neuronal survival. Finally, synaptic transmission in the penumbra was abolished within 50 min of focal OGD application. These results suggest that this in vitro model mimics events that occur during focal ischemia in vivo and can be used to determine the efficacy of therapeutics that target neuronal survival in the core and/or penumbra.
Richard
Marc J P
MJ
Department of Biomedical Science, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada.
Saleh
Tarek M
TM
El Bahh
Bouchaib
B
Zidichouski
Jeffrey A
JA
D000818:Animals; D000983:Antipyrine / Q000031:analogs & derivatives / Q000494:pharmacology; D002545:Brain Ischemia / Q000188:drug therapy / Q000209:etiology* / Q000503:physiopathology; D015687:Cell Hypoxia / Q000187:drug effects / Q000502:physiology; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D003470:Culture Media / Q000378:metabolism; D000077553:Edaravone; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D005947:Glucose / Q000172:deficiency / Q000378:metabolism; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D008959:Models, Neurological; D009474:Neurons / Q000187:drug effects / Q000473:pathology / Q000502:physiology; D018696:Neuroprotective Agents / Q000494:pharmacology; D010100:Oxygen / Q000378:metabolism; D018408:Patch-Clamp Techniques; D017397:Prefrontal Cortex / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D046509:Tissue Culture Techniques / Q000295:instrumentation / Q000379:methods*
D003470:Culture Media; D018696:Neuroprotective Agents; D005947:Glucose; D000077553:Edaravone; D010100:Oxygen; D000983:Antipyrine