Effects of a single dose of erythropoietin on subsequent seizure susceptibility in rats exposed to acute hypoxia at P10.
OBJECTIVE
To determine if posthypoxia treatment with erythropoietin (EPO) has protective effects against subsequent susceptibility to seizure related neuronal injury in rat pups subjected to acute hypoxia at P10.


METHODS
Four groups of rats were manipulated at P10, as described below, then all received kainic acid (KA) (10 mg/kg i.p.) at P29: Hypoxia-NS-KA group (n = 11): subjected to acute hypoxia (down to 4% O2), and then immediately received saline i.p. Hypoxia-EPO-KA group (n = 10): subjected to acute hypoxia and then immediately received EPO (1,000 U/Kg i.p.). Normoxia-NS-KA group (n = 11): sham manipulated and injected with saline. Normoxia-EPO-KA group (n = 10): sham manipulated then immediately injected with EPO (1000 U/Kg i.p.). After receiving KA at P29, all rats were monitored using videotape techniques, and were sacrificed at P31. TUNEL and Hoechst stains to assess for apoptosis, and regular histology for hippocampal cell counts were performed.


RESULTS
Administration of the single dose of erythropoietin directly after an acute hypoxic event at P10 resulted at P29 in increased latency to forelimb clonus seizures, reduced duration of these seizures, protection against hippocampal cell loss, and decreased hippocampal apoptosis in the Hypoxia-EPO-KA group as compared to the Hypoxia-NS-KA group.


CONCLUSIONS
These data support the presence of favorable protective effects of erythropoietin against the long-term consequences of acute hypoxia in the developing brain and raise the possibility of its investigation as a potential neuroprotective agent after human neonatal hypoxic encephalopathy.
Mikati
Mohamad A
MA
Department of Pediatrics, American University of Beirut, Beirut, Lebanon. mamikati@aub.edu.lb
El Hokayem
Jimmy A
JA
El Sabban
Marwan E
ME
D000818:Animals; D000831:Animals, Newborn; D002452:Cell Count; D004195:Disease Models, Animal; D004198:Disease Susceptibility / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004921:Erythropoietin / Q000008:administration & dosage / Q000494:pharmacology*; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D000860:Hypoxia / Q000378:metabolism* / Q000473:pathology; D002534:Hypoxia, Brain / Q000517:prevention & control; D007608:Kainic Acid / Q000494:pharmacology; D018696:Neuroprotective Agents / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D012640:Seizures / Q000139:chemically induced* / Q000473:pathology / Q000517:prevention & control*
D018690:Excitatory Amino Acid Agonists; D018696:Neuroprotective Agents; D004921:Erythropoietin; D007608:Kainic Acid