Effect of hypothermic post-treatment on hypoxic-ischemic striatal injury, and normal striatal development, in neonatal rats: a stereological study.
Fundamental questions remain about the optimal temperature, duration, and mode of delivery that provide the best striatal neuroprotection from hypothermia after perinatal hypoxia-ischemia. This study used stereological methods to investigate whether a mild (i.e. 2 degrees C) or a moderate (5 degrees C) decrease in whole body temperature, for 6 h immediately postinsult, was neuroprotective for striatal medium-spiny neurons after perinatal hypoxia-ischemia in the rat. This study also investigated whether moderate hypothermia had any effect on normal striatal development. Hypoxia-ischemia or sham hypoxia-ischemia was induced on postnatal day (PN) 7. Pups were kept either normothermic, mildly hypothermic, or moderately hypothermic for 6 h immediately postinsult. The absolute number of striatal medium-spiny neurons was calculated using modern stereological methods. There was no significant difference in the absolute number of medium-spiny neurons in the right striatum after either mild hypothermia or moderate hypothermia. There was also no significant difference in the absolute number of medium-spiny neurons between the control normothermic and the control moderately hypothermic pups. The latter results suggest that moderate hypothermia for 6 h immediately postinsult may be a safe treatment for striatal medium-spiny neurons. Yet, neither mild nor moderate hypothermia alone for 6 h immediately posthypoxia-ischemia is neuroprotective for striatal medium-spiny neurons.
Covey
Matthew V
MV
Department of Anatomy and Structural Biology, University of Otago, 9054 Dunedin, New Zealand.
Oorschot
Dorothy E
DE
D000818:Animals; D000831:Animals, Newborn; D001479:Basal Ganglia / Q000098:blood supply / Q000254:growth & development / Q000473:pathology*; D001831:Body Temperature; D002452:Cell Count; D004195:Disease Models, Animal; D007036:Hypothermia, Induced / Q000379:methods*; D020925:Hypoxia-Ischemia, Brain / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D009474:Neurons / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors