Expression of glutamate receptor 1 and excitatory amino acid transporters 2 in hypertrophic cardiomyocytes in rats
Li Guofu, Liu Ziyou, Chen Guangxian, Du Shangming, Liang Mengya, Yao Jianping, Wu Zhongkai
Published 2015-04-08
Cite as Chin J Exp Surg, 2015,32(04): 808-810. DOI: 10.3760/cma.j.issn.1001-9030.2015.04.050
Abstract
ObjectiveTo investigate the expression of N methyl D asparate receptor 1(NMDAR1) and excitatory amino acid transporters 2(EAAT 2)in hypertrophic cardiomyocytes in rats.
MethodsUsing abdominal aortic- occluded myocardial hypertrophy model,64 male F344 rats were randomly assigned into post- occlusion 2 weeks, 3 weeks, 4 weeks and 8 weeks groups.Each group was further divided as the study subgroup or control subgroup. Myocardial hypertrophy was comfirmed by echocardiography, and connexin43(Cx43), NMDAR1 and EAAT 2 expression was detected by immunofluorescence.
ResultsMyocardial hypertrophy was confirmed with the examinations of IVSTd and PWLVd. The most thickness hypertrophy heart was found at 3rd week after aortic- occlusion[(1.72±0.17)mm vs.(1.29±0.24)mm, and(2.12±0.12)mm vs.(1.43±0.37)mm,P< 0.05 for all].Area,% and IA,% of the expression of myocardial NMDAR1 and EAAT 2 were significantly higher in hypertrophy myocardium at 3rd and 4th week after aortic- occlusion(at 4th week after aortic- occlusion, for NMDAR1:1.51±0.45 vs.0.79± 0.63 and 1.11±0.29 vs.0.60±0.17,and for EAAT 2:1.69±0.47 vs.0.99±0.53 and 1.31±0.39 vs. 0.90±0.47,P< 0.05 for all).Area,% and IA% of the expression of Cx43 in myocardium were significantly higher in hypertrophy myocardium at 3rd,4th and 8th week after aortic- occlusion(at 4th week after aortic- occlusion, 2.51±0.85 vs.1.11±0.33, and 1.94±0.66 vs.0.80±0.55,P< 0.05).
ConclusionThe up-regulation of NMDAR1 and EAAT 2 in hypertrophic cardiomyocytes suggested that glutamate signal system participated in the myocardial hypertrophy remodeling process. The effects of NMDAR1 and EAAT 2 decreased at 8th week after hypertrophy remodeling, and those of Cx43 resustained for relatively longer time.
Key words:
Glutamate receptor; Glutamate transporter; Connexin43; Myocardial Hypertrophy
Contributor Information
Li Guofu
The Second Department of Cardiac Surgery, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
Liu Ziyou
Chen Guangxian
Du Shangming
Liang Mengya
Yao Jianping
Wu Zhongkai