New Modes of GPCR Signalling

NMDA Receptors Subunit NR2B Messenger Rnas Expression with
Cognitive Dysfunction after Bilateral Common Carotid Artery Occlusion
in the Adult Rats
Lianjun Guo, Yang Cheng, Bo Zhao
Department of Pharmacology, Tongji Medical College, Huazhong University of Science
and Technology, Wuhan 430030, P.R. China
Aim: To explore whether and how NR2B mRNA may be altered in global incomplete
chronic cerebral ischemic rat model. Methods: Chronic cerebral hypoperfusion in Male
SD rats was performed by permanent occlusion of the bilateral common carotid artery
(2VO) for 30 days. Morris water maze was used to measure spatial learning and
memory performance. Electrophysiological equipments were used to record long-term
potentiation (LTP). In situ hybridization and reverse transcriptase polymerase chain
reaction (RT-PCR) assays were used to investigate NR2B mRNA may be altered in
global incomplete chronic cerebral ischemic rat model. Results: the spatial learning
and memory function of rats attenuated by longer escape latency, shorter time spent in
the target quadrant and impaired long term potentiation (LTP) after chronic cerebral
ischemia. In the in situ hybridization experiment, NR2B declined to 58.82% and
45.60% of the control values in the neocortex and hippocampal region separately after
chronic cerebral ischemia. NR2B mRNA in the hippocampal region and neocortex was
markedly down regulated by ischemia, reaching 43.57% and 30. 05% of the control
values respectively in the semi-quantitative RT-PCR experiment. Conclusions: Our data
suggest that NR2B subunit plays an important role for the spatial learning and memory
function of rats.
Key Words: NR2B messenger RNA; hippocampal neurons; cerebral ischemia
Acknowledgments: This work was supported by grants from the National Natural
Science Foundation of China (NSFC, No. 30772559) to Lianjun Guo
Author: Lianjun Guo , Tel:02783691763, Email: gljyl@yahoo.com.cn