Infarct volume and functional outcome after pre- and postoperative administration of metyrapone, a steroid synthesis inhibitor, in focal brain ischemia in the rat.
High blood levels of glucocorticoids are associated with increased mortality, confusion and poor functional outcome in stroke patients. It has been proposed that inhibition of glucocorticoids in acute stroke might be beneficial, but experimental data are conflicting and no long-term follow-up study has been reported. We have studied whether pre- or postoperative administration of metyrapone, a steroid synthesis inhibitor, can influence long-term outcome after ligation of the right middle cerebral artery (MCA) distal to the striatal branches in hypertensive rats. Metyrapone (200 mg/kg) was administered either 30 min before or 1, 12 and 24 h after MCA occlusion. Limb placements and ability to traverse a rotating pole were evaluated pre- and postoperatively. Infarct size, histology and GFAP immunoreactivity were evaluated on 5 microm coronal sections from brains perfused in situ 4 weeks after the ischemic event. Pretreatment did not influence outcome, whereas postoperative administration of metyrapone significantly increased infarct volume (P < 0.05). Post-treated rats performed significantly worse than vehicle-treated rats on the rotating pole 3 weeks after the operation (P < 0.05). Our results do not support the hypothesis that inhibition of glucocorticoid synthesis improves outcome after cerebral ischemia.
Risedal
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A
Department of Clinical Neurosciences, Section for Experimental Neurology, University Hospital, Lund, Sweden.
Nordborg
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C
Johansson
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BB
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects* / Q000502:physiology*; D002545:Brain Ischemia / Q000473:pathology* / Q000523:psychology*; D002540:Cerebral Cortex / Q000473:pathology; D002544:Cerebral Infarction / Q000473:pathology* / Q000523:psychology*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D005911:Gliosis / Q000473:pathology; D007091:Image Processing, Computer-Assisted; D008297:Male; D008797:Metyrapone / Q000494:pharmacology*; D020768:Middle Cerebral Artery / Q000502:physiology; D051381:Rats; D011918:Rats, Inbred SHR; D013787:Thalamic Nuclei / Q000473:pathology
D005904:Glial Fibrillary Acidic Protein; D008797:Metyrapone