All issues > Volume 45(5); 2002

Original Article

J Korean Pediatr Soc. 2002;45(5):629-636. Published online May 15, 2002.

Characteristics of Seizures and Neuronal Nitric Oxide Synthase Expression of Hippocampus in Hyperthermia-Induced Seizures of Developing Rat

Doo-Kwun DK Kim¹, Dong-Keun DK Jung²

¹Department of Pediatrics, Dongguk University College of Medicine, Kyungju, Korea
²Department of Physiology, Donga University College of Medicine, Busan, Korea

Correspondence Doo-Kwun DK Kim ,Email: pedepi@hotmail.com

Abstract

Purpose
: Our study was aimed to investigate the characteristics of seizures as well as to determine whether the expression of neuronal nitric oxide synthase expression(nNOS) of hippocampus has an affect in the hyperthermic seizure in developing rat.
Methods
: Hyperthermic seizures were repeatedly induced twice a week for four weeks in 20-day old Spraque-Dowley rats. Fifty two rats were used as a hyperthermic group and 30 rats used as a normothermic control group. Hyperthermic seizures were induced in a water bath at 45℃±1 for 4 min. The characteristics of seizures were recorded. Using western blot, hippocampal nNOS expression was measured in normothermic control, hyperthermic non-seizure, and hyperthermic seizure groups, respectively.
Results
: Eighty seven percent of hyperthermia exposed rats showed generalized tonic-clonic seizure most frequently. The duration of seizure was ranged from 12 to 145 sec(mean 55 sec) and the latency to seizure ranged from 158 to 240 sec(mean 204 sec). The duration of seizure was prolonged but there was no significant difference in the seizure latency as the rat exposed more number of hyperthermia. Interestingly, the expression level of hippocampal nNOS in hyperthermic seizure and hyperthermic non-seizure groups was not different from each other, however, the expression in these groups was lower than that of the control group.
Conclusion
: Our results indicate that nNOS do not have an affect in this repeated hyperthermic seizures. Further studies are required to clarify a role of nNOS in hyperthermic seizure.

Keywords :Hyperthermic seizures, Neuronal nitric oxide synthase, Spraque-Dowley rat