Increase in nitric oxide in the hypoxic-ischemic neonatal rat brain and suppression by 7-nitroindazole and aminoguanidine.
We measured the changes in nitric oxide (NO) metabolites in the brains of neonatal rats with hypoxic-ischemic damage. There were two peaks of NO metabolites in the lesioned side of the cortex without treatment: one during hypoxia and the other during the re-oxygenation period. Prehypoxic treatment with 7-nitroindazole, a selective neuronal NO synthase inhibitor, suppressed both peaks of NO metabolites, whereas prehypoxic treatment with aminoguanidine, a selective inducible NO synthase inhibitor, partially suppressed only the peak in the re-oxygenation period. These data suggest different roles of neuronal and inducible NO synthases in the pathogenesis of hypoxic-ischemic encephalopathy.
Higuchi
Y
Y
Department of Pediatrics, Faculty of Medicine, Kyoto University, Japan. hig@kuhp.kyoto-u.ac.jp
Hattori
H
H
Kume
T
T
Tsuji
M
M
Akaike
A
A
Furusho
K
K
D000818:Animals; D000831:Animals, Newborn; D001923:Brain Chemistry / Q000187:drug effects / Q000502:physiology; D002545:Brain Ischemia / Q000201:enzymology / Q000378:metabolism*; D004790:Enzyme Induction / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006146:Guanidines / Q000494:pharmacology*; D002534:Hypoxia, Brain / Q000201:enzymology / Q000378:metabolism*; D007191:Indazoles / Q000494:pharmacology*; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors* / Q000096:biosynthesis*; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D004791:Enzyme Inhibitors; D006146:Guanidines; D007191:Indazoles; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; C496322:Nos1 protein, rat; C496318:Nos2 protein, rat; C004479:pimagedine; C080122:7-nitroindazole