Role of Cx43 gene in the process of myocardialization of proximal outflow tract septum in the mouse heart
- VernacularTitle:Cx43基因对近端流出道隔心肌化过程的调控机制
- Author:
Xiaoqing ZHAO
;
Guoying HUANG
;
Lijian XIE
;
Tao PENG
;
Ping CHEN
;
Guomin ZHOU
- Publication Type:Journal Article
- Keywords:
Genes,Cx43;
Gene knockout;
Apoptosis;
Neural crest
- From:
Chinese Journal of Pathophysiology
2000;0(12):-
- CountryChina
- Language:Chinese
-
Abstract:
AIM: To investigate the role of Cx43 in the myocardialization of the proximal outflow tract(OFT) septum in the mouse heart.METHODS: C57/BL6 mice of ED11.5 to 1 day after birth were used in this study,which included Cx43 knockout homozygotes((Cx43-/-)),heterozygotes((Cx43+/-)) and wildtypes((Cx43+/+)).Pathohistological analysis was used to examine the structure of the hearts.The expression of alpha-sarcomeric actin(?-SCA),active caspase-3 and activator protein-2(AP-2) were detected by immunohistochemistry.RESULTS: Most(Cx43-/-) mice died within 24 h after birth with a swelling and blockage of the conotruncal region,which led to the obstruction of OFT and enlargement of right ventricle.HE staining showed plenty of abnormal tissues in this region forming many pouches.No apparent malformations were observed in(Cx43+/-) and(Cx43+/+) mice.The expression of ?-SCA in the proximal OFT septum was delayed obviously in(Cx43-/-).The apoptotic cells existed in the proximal OFT septum of(Cx43+/+) mostly during ED12.5 to ED15.5.However,there were less apoptotic cells observed in(Cx43+/-),and few in(Cx43-/-).The expression of AP-2,marker of neural crest cells,was increased in (Cx43-/-) and abnormally located in the proximal OFT septum.CONCLUSIONS: Cx43 KO mice are characterized by hyperplasia in conotruncal region,which may be associated with the delayed myocardialization of OFT septum.The decreased apoptosis and the abnormal distribution of cardiac neural crest cells are likely to contribute to the abnormal myocardialization in mice with Cx43 defects.
