The Immunohistochemical Expression of Neuronal Nitric Oxide Synthase in Rat Hippocampus after Pentylenetetrazole-Induced Seizures.
- Author:
Doo Kwun KIM
1
;
Tae Jung JANG
Author Information
1. Department of Pediatrics, College of Medicine, Dongguk University, Kyongju, Korea. pedepi@dumc.or.kr
- Publication Type:Original Article
- Keywords:
Neuronal nitric oxide synthase;
NOS inhibitor;
Immunohistochemistry;
Pentylenetetrazole;
Seizure;
Rat
- MeSH:
Animals;
Hippocampus*;
Humans;
Immunohistochemistry;
Male;
Myoclonus;
Neurons*;
Nitric Oxide;
Nitric Oxide Synthase Type I*;
Pentylenetetrazole;
Rats*;
Rats, Sprague-Dawley;
Seizures*
- From:Journal of the Korean Pediatric Society
2001;44(12):1432-1440
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: In order to determine the effect of neuronal nitric oxide synthase(nNOS) in seizure-related neuronal vulnerability of the hippocampus, the expression patterns of nNOS were examined in pentylenetetrazole(PTZ)-induced seizure groups and in PTZ seizure groups which were pretreated with nNOS inhibitors. METHODS: Male Sprague-Dawley rats weighing 200-300 g were used in PTZ(40 mg/kg)-induced seizure experiments. A specific inhibitor, 50 mg/kg 7-nitroindazole(7-NI), and a non-specific inhibitor, 50 mg/kg nitro-L-arginine(L-NA) were treated 30 min before the administration of PTZ to block nNOS. nNOS expression was evaluated by using immunohistochemical staining in the hippocampus of each group. RESULTS: The onset time of the first myoclonic jerk was markedly delayed in the 7-NI and the L- NA pretreated groups in comparison to the PTZ group. In addition, 7-NI markedly suppressed the severity of PTZ-induced seizures. The expression of nNOS in the hippocampal CA3 area was higher than that in CA1 area in the PTZ treated groups. In the L-NA pretreated groups, the expression levels in the CA3 and CA1 areas were lower than those of the PTZ treated groups. Interestingly, in the 7-NI pretreated groups, the nNOS expression levels in CA1 and CA3 areas were makedly lower than those of PTZ and L-NA pretreated groups. There was no expression in CA2 area of all groups. CONCLUSION: These results suggest that the hippocampal neurons expressing nNOS may be vulnerable to PTZ-induced seizures and that nNOS may play an important role in seizure-related neuronal vulnerability.
