[Alteration of the expression of rat cardiac Galphaq/11 and Gialpha2 proteins during endothelin-1 pre-treatment].
The present study was undertaken to explore the mechanism of G protein-mediated signal transduction pathway during endothelin-1 (ET-1) pre-treatment and ischemic preconditioning (IP). Rats were divided into four groups: ET-1, IP, ischaemia-reperfusion (IR) and control groups. ET-1 pre-treatment model was prepared by administrating 0.5 nmol/(L.kg) ET-1 into rat left ventricle, whereas IP model was prepared by ligating the left coronary artery for 5 min followed by 30 min reperfusion. All the animals were subjected to 60 min regional ischaemia and 30 min reperfusion alternately and then parameters of ventricular arrhythmia and expression of cardiac Galphaq/11 and Gialpha2 were measured. The results showed that the scores of ventricular arrhythmia decreased significantly in both ET-1 and IP treated groups as compared with IR group. In comparison with control group, Galphaq/11 increased by 77.8% (P<0.05) and 110.6% (P<0.01) in IP and ET-1 group respectively. Gialpha2 showed no significant difference in IP group, while it decreased by 31.0% (P<0.01) in ET-1 group. In conclusion, activation of G alphaq/11 may be related to the protecting mechanism of ET-1 pre-treatment and IP, whereas Gialpha2 may only play a role in ET-1 pre-treatment.
Wang
X T
XT
Department of Pathophysiology, Beijing Medical University, Beijing 100083, China. wxt@mailk.bjmu.edu.cn
Yang
X L
XL
Lu
L Q
LQ
Zhang
L K
LK
Sun
Y P
YP
Wang
J Y
JY
Wu
L L
LL
D000818:Animals; D019332:Endothelin-1 / Q000494:pharmacology*; D051960:GTP-Binding Protein alpha Subunit, Gi2; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000378:metabolism*; D043802:GTP-Binding Protein alpha Subunits, Gq-G11; D020962:Heterotrimeric GTP-Binding Proteins / Q000378:metabolism*; D019157:Ischemic Preconditioning, Myocardial; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D019332:Endothelin-1; D011518:Proto-Oncogene Proteins; D051960:GTP-Binding Protein alpha Subunit, Gi2; D019206:GTP-Binding Protein alpha Subunits, Gi-Go; D043802:GTP-Binding Protein alpha Subunits, Gq-G11; C498017:Gnai2 protein, rat; D020962:Heterotrimeric GTP-Binding Proteins