GM1 stabilizes expression of NMDA receptor subunit 1 in the ischemic hemisphere of MCAo/reperfusion rat.
OBJECTIVE
To determine the protective effect of monosialoganglionside (GM1) and evaluate the influence of GM1 on expression of N-methyl-D-aspartate receptor subunit 1 (NMDAR1) in Sprague-Dawley (SD) rats with focal cerebral ischemia-reperfusion (I/R).


METHODS
Left middle cerebral artery (MCA) was occluded by an intraluminal suture for 1 h and the brain was reperfused for 72 h in SD rats when infarct volume was measured, GM1 (10 mg/kg) was given ip (intraperitoneally) at 5 min (group A), 1 h (group B) and 2 h (group C) after MCA occlusion (MCAo). Expression of NMDAR1 was detected by Western blot at various time after reperfusion (4 h, 6 h, 24 h, 48 h and 72 h) in ischemic hemispheres of the rats with or without GM1 administered.


RESULTS
(1) Adjusted relative infarct volumes of groups A and B were significantly smaller than that of group C and the control group (P<0.01 and P<0.05, respectively). (2) Expression level of NMDAR1 was temporally high at 6 h after reperfusion, and dipped below the normal level at 72 h after reperfusion. GM1 at 5 min after MCAo significantly suppressed the expression of NMDAR1 at 6 h after reperfusion (P<0.05 vs the control). At 72 h after reperfusion, the NMDAR1 expression level of rats treated with GM1 administered (at 5 min or 2 h after MCAo) was significantly higher than that of the control (P<0.05).


CONCLUSIONS
GM1 can time-dependently reduce infarct volume in rats with focal cerebral I/R partly through stabilizing the expression of NMDAR1.
Liu
Jian-ren
JR
Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China. Liujianren@medmail.com.cn
Ding
Mei-ping
MP
Wei
Er-qing
EQ
Luo
Jian-hong
JH
Song
Ying
Y
Huang
Jian-zheng
JZ
Ge
Qiu-fu
QF
Hu
Hua
H
Zhu
Li-jun
LJ
D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology / Q000517:prevention & control; D005677:G(M1) Ganglioside / Q000494:pharmacology* / Q000627:therapeutic use; D005786:Gene Expression Regulation / Q000187:drug effects*; D008297:Male; D020768:Middle Cerebral Artery / Q000601:surgery*; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D021122:Protein Subunits / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D015427:Reperfusion Injury / Q000378:metabolism* / Q000473:pathology / Q000517:prevention & control; D016896:Treatment Outcome
D005677:G(M1) Ganglioside; D021122:Protein Subunits; D016194:Receptors, N-Methyl-D-Aspartate