The Induction of Immediate Early Genes and Phosphorylation of p42, p44 MAPK and Elk-1 by Kainic Acid in Developing Rat Hippocampus.
- Author:
Hee Yeon JUNG
1
;
Soo Jin KIM
;
Jong Heun KIM
;
Sun Ju CHUNG
;
Joo Bae PARK
;
Yong Sik KIM
;
Soo Churl CHO
Author Information
1. Department of Psychiatry, Seoul National University College of Medicine, Seoul, Korea.
- Publication Type:Original Article
- Keywords:
Development;
Kainic acid;
Rat brain;
Immediate early gene;
Mitogen activated protein kinase(MAPK);
Elk-1
- MeSH:
Adult;
Aging;
Animals;
Blotting, Northern;
Brain;
Genes, Immediate-Early*;
Hippocampus*;
Humans;
Immunoblotting;
Injections, Intraperitoneal;
Kainic Acid*;
Mitogen-Activated Protein Kinase 3*;
Phosphorylation*;
Rats*;
Seizures;
Signal Transduction
- From:Journal of Korean Neuropsychiatric Association
1999;38(4):894-903
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
OBJECTIVES: In order to investigate the maturational process of intracellular signal transduction system in rat brain, we studied the induction of the immediate early genes(IEGs)c-fos, junB, and TIS1 in each developmental stage after kainic acid(KA)induced seizure in young rat hippocampus and then compared these with the results after electroconvulsive shock(ECS) And to elucidate the induction mechanism of c-fos via mitogen-activated protein kinase(MAPK)by KA in each developmental stage, we investigated the phosphorylation of p42, p44 MAPK and Elk-1 after KA treatment in young rat hippocampus. METHODS: We examined the induction patterns of IEGs by northern blot analysis, and the phosphorylation of p42, p44 MAPK and Elk-1 by immunoblotting in rat hippocampus at post-natal day 7, 14, and 21(P7, P14 & P21) respectively after intraperitoneal injection of KA. RESULTS: Unlike ECS, KA did not induce c-fos, junB, and TIS1 in P7 hippocampus. But these genes were apparently induced at P14 and to an adult level at P21. These three IEGs showed similar temporal patterns of induction in each developmental stage. Although the basal level of phosphorylated 42p, 44p MAPK was considerable in P7 rat hippocampus, the increase of phosphorylation after KA treatment was observed at P14 . While the phosphorylation of Elk-1 was detected with high basal level in P7 rat, the amount of phosphorylated Elk-1 was not changed after KA treatment. CONCLUSION: Our results suggest that the differences in IEGs induction patterns between KA and ECS may be due to the differences in the activated signal transduction pathways. And our results also implicate that the signal transduction system involved in MAPK phosphorylation after KA treatment mature with aging and c-fos induction via MAPK activation may be regulated through some pathways other than Elk-1 in rat hippocampus.
