Selective alteration of expression of Na+/Ca2+ exchanger isoforms after transient focal cerebral ischemia in rats.
The Na+/Ca2+ exchanger (NCX) is an antiporter located in the plasma membrane of many cells, which can maintain the intracellular Ca(2+) homeostasis. Some studies have shown the close relationship of NCX and cerebral ischemia. But controversial results were obtained. Three NCX isoforms, NCX1, NCX2, and NCX3 were distributed selectively in central nervous system, which suggests that each isoform may have different function in cerebral ischemia. In this study we investigated the time-related alteration of gene and protein expressions of NCX1, NCX2, and NCX3 in rat brain cortex after 2 h of transient middle cerebral artery occlusion (tMCAO). Reverse transcription-polymerase chain reaction (RT-PCR) was used to investigate the mRNA levels of each NCX isoform at 2, 6, 12, and 24 h of reperfusion, respectively. Western blot was used to measure the protein expressions of each NCX isoform at 2, 12, and 24 h of reperfusion, respectively. The results showed that NCX1 mRNA level was reduced by 42.1% and 27.8%, respectively, at 2 and 6h of reperfusion and restored to normal level at 12 and 24 h of reperfusion. NCX1 protein was decreased by 36.6% at 2 h of reperfusion and recovered at 12 and 24 h of reperfusion. The mRNA and protein levels of NCX2 and NCX3 did not change significantly over time. These results suggest that NCX1 might play an important role in transient focal cerebral ischemia.
Li
Liao-Liao
LL
Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Sun
Li-Na
LN
Zhou
Hong-Yi
HY
Li
Zheng-Bin
ZB
Wang
Xiao-Liang
XL
D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism; D020244:Infarction, Middle Cerebral Artery / Q000150:complications; D002546:Ischemic Attack, Transient / Q000209:etiology / Q000378:metabolism*; D008297:Male; D026901:Membrane Transport Proteins / Q000096:biosynthesis* / Q000235:genetics; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D019831:Sodium-Calcium Exchanger / Q000096:biosynthesis* / Q000235:genetics
D026901:Membrane Transport Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; C110927:Slc8a2 protein, rat; C491102:Slc8a3 protein, rat; D019831:Sodium-Calcium Exchanger; C110374:sodium-calcium exchanger 1