Why Model Strokes ? Gaetano

In this issue of Stroke, Professor Laszlo Molnar and coworkers describe another experimental model of stroke. An apparently reversible form of embolic intravascular occlusion may now be added to previous tabulations of various methods and outcomes. Professor Molnar and coworkers have previously validated their model by light microscopic criteria to show morphologic resemblance to ischemic pathology in humans. In their current report, Molnar et al use multiple pathophysiologic monitors to show ischemic changes and their reversibility before development of permanent damage. What is the significance, clinical relevance, and therapeutic implications of yet another published method for producing strokes in animals in this era of aggressive animal rights activism when we have transmitted (computed tomography [CT]) and emitted (positron emission tomography [PET] and singlephoton emission computed tomography [SPECT]) radiation scans and nuclear magnetic resonance imaging (MRI) of the brain capable of deriving morphologic, physiologic, and even metabolic data directly from patients? There are several advantages to the use of animal models. Most of our knowledge to date about the minute-to-minute pathogenesis of cerebral ischemia and infarction is based on detailed studies in animal models.The use of standardized animals selected for uniformity removes the uncontrollable variables encountered in human disease and permits relatively simple analysis and assessment of causeeffect relations between ischemia and infarction, pathogenesis and treatment. Certain models permit quantitative gradation of both severity and duration of the ischemic insult with infarct size in pathologic specimens both with and without specific treatment variables. Despite the absence of a clinically proven efficacious treatment for acute strokes in humans,many therapies including barbiturates, naloxone, calcium channel blockers, and even extracranialintracranial bypass surgery have proven effective in reducing lesion size in animal models compared with untreated controls. New therapeutic approaches that