Corticotropin-releasing hormone is a rapid and potent convulsant in the infant rat.
Corticotropin-releasing hormone (CRH) administered into the cerebral ventricles of rats during the first postnatal week caused a specific and stereotyped behavior sequence: rhythmic chewing and licking (jaw myoclonus) were followed by 'limbic'-type seizures. The onset of the seizures was much more rapid (2-45 min vs 3-7 h) than in adult rats, and the convulsant doses were much lower (50 x 10(-12) mol per gram brain weight vs 750 x 10(-12) mol per gram brain weight in adults). CRH potency in inducing seizures varied inversely with age. CRH-induced seizures occurred prior to any changes in serum corticosterone, and were eliminated by the administration of a CRH antagonist, as well as of phenytoin. Electrocorticographic correlates of CRH-induced behaviors in the infant rat were inconsistent, suggesting a subcortical origin of CRH-induced paroxysmal events in the immature brain.
Department of Neurology, University of Southern California, Los Angeles.
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Baram
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Schultz
D000375:Aging; D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000187:drug effects / Q000254:growth & development* / Q000503:physiopathology; D003292:Convulsants / Q000633:toxicity*; D003346:Corticotropin-Releasing Hormone / Q000633:toxicity*; D004569:Electroencephalography; D051381:Rats; D011919:Rats, Inbred Strains; D012640:Seizures / Q000139:chemically induced / Q000503:physiopathology*
D003292:Convulsants; D003346:Corticotropin-Releasing Hormone