Effect of indomethacin on edema following single and repetitive cerebral ischemia in the gerbil.
OBJECTIVE
Repetitive periods of cerebral ischemia result in more severe injury than a single period of ischemia of similar total duration. We investigated the possibility of prostaglandin mediation of this increased injury by attempting to modify brain edema formation with indomethacin pretreatment.


METHODS
Under halothane/N2O anesthesia, groups of gerbils underwent bilateral carotid occlusion to induce forebrain ischemia. Group I underwent a single 15-minute period of carotid occlusion. Group II underwent three 5-minute periods of occlusion at hourly intervals. Groups III and IV were similar to groups I and II, respectively, but received 0.2 mg/kg indomethacin before carotid occlusion. Cortical and cerebellar water and sodium contents were determined in control animals (n = 6) at time zero and in experimental animals 24, 48, and 72 hours after ischemia (n = 6-10 gerbils/group at each time point).


RESULTS
Cortical water and sodium contents in group II peaked 48 hours after insult (82.15 +/- 0.31% and 420 +/- 14 meq/kg dry wt, respectively) and were significantly higher than control and group I values at both 24 and 48 hours. Cortical water did not change from control in group I animals. Indomethacin pretreatment significantly attenuated increases in water and sodium content seen at 48 hours in gerbils undergoing repetitive ischemia (peak 80.02 +/- 0.45% and 300 +/- 39 meq/kg dry wt), but did not affect mortality.


CONCLUSIONS
Indomethacin lessens edema after repetitive cerebral ischemia, suggesting that elevations of cyclooxygenase products are responsible, at least in part, for severe brain edema following repetitive ischemia.
Department of Pediatrics, University of Michigan, Ann Arbor.
K S
KS
Deluga
F B
FB
Plötz
A L
AL
Betz
D000818:Animals; D001923:Brain Chemistry; D002545:Brain Ischemia / Q000150:complications* / Q000503:physiopathology; D004195:Disease Models, Animal; D004487:Edema / Q000209:etiology* / Q000503:physiopathology; D005849:Gerbillinae; D007213:Indomethacin / Q000494:pharmacology*; D008297:Male; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism / Q000502:physiology; D011453:Prostaglandins / Q000378:metabolism; D013997:Time Factors; D014882:Water-Electrolyte Balance / Q000187:drug effects / Q000502:physiology
D011453:Prostaglandins; D011451:Prostaglandin-Endoperoxide Synthases; D007213:Indomethacin