NR2B-pERK1/2-pElk-1 signaling contributes to the avoidance learning and memory of rats.
- Author:
Xu-Hong CHEN
1
;
Si-Yun SHU
;
Zhen-Jiang LIANG
;
Xin-Min BAO
;
Li-Xue CHEN
;
Yong-Ming WU
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Avoidance Learning; physiology; Dimethyl Sulfoxide; pharmacology; Extracellular Signal-Regulated MAP Kinases; metabolism; Male; Maze Learning; physiology; Memory; physiology; Piperidines; pharmacology; Rats; Rats, Sprague-Dawley; Receptors, N-Methyl-D-Aspartate; metabolism; ets-Domain Protein Elk-1; metabolism
- From: Chinese Journal of Applied Physiology 2007;23(1):121-125
- CountryChina
- Language:Chinese
-
Abstract:
AIMTo investigate whether NR2B-pERK1/2-pElk-1 signaling contributes to the Y-maze learning and memory of rat brain.
METHODS45 adult male SD rats were divided into 4 groups: (1) Ifenprodil peritoneal injection group (Ifenprodil ip, n = 14); (2) DMSO peritoneal injection group(DMSO ip, n = 15); (3) Ifenprodil cerebral ventricle injection group (Ifenprodil ic, n = 8); (4) DMSO cerebral ventricle injection group(DMSO ic, n = 8). Y-maze training and test were used as an learning and memory enhancing stimulus. Immunohistochemical and Western blotting methods were used for detecting pERK1/2 and pElk-1 expression intensity of different brain regions.
RESULTSCompared with the DMSO ip group, the ifenprodil ip group showed no change on the Y-maze learning score (P > 0.05), but its Y-maze memory score tested 24 after learning decreased (P < 0.05). Ifenprodil peritoneal injection made brain pERK1/2 and pElk-1 expression decreased generally. In hippocampus, marginal division of striatum(MrD), amygdala,these changes were more significant (P < 0.05). Compared with the DMSO ic group, the reconsolidation of Y-maze memory tested 6 hours after ifenprodil injection was impaired in ifenprodil ic group (P < 0.05). The OD value of pERK1/2 and pElk-1 positive bands in ifenprodil ic group attenuated generally. The pElk-1 positive bands of caudate putamen and MrD almost disappeared in ifenprodil ic group.
CONCLUSIONNR2B is essential for the formation of long-term memory, reconsolidation of Y-maze memory. The deactivation of NR2B by ifenprodil will impair these courses. Meanwhile, the deactivation of NR2B attenuates pERK1/2 and pElk-1 expression of learning and memory related regions after Y-maze learning and memory reconsolidation test. In MrD and caudate putamen, the pElk-1 expression are completely blocked by ifenprodil after memory reconsolidation test.