Messenger RNA levels of guanine nucleotide-binding proteins are reduced in the ventricle of cardiomyopathic hamsters.
The expression of guanine nucleotide-binding protein (G-protein) genes (Gs alpha, Go alpha, Gi alpha 1, Gi alpha 2, and Gi alpha 3) was examined in the ventricle of cardiomyopathic Syrian hamsters of the Bio14.6 strain (10-35 weeks old). Northern blot analysis of total cellular RNA revealed that all G-protein genes except Gi alpha 1 were expressed in the ventricle of Syrian hamsters. Gs alpha and Gi alpha 2 genes were abundantly expressed. The expression levels of the Gs alpha and Gi alpha 2 messenger RNAs in Bio14.6 ventricles were lower than the levels in ventricles of the F1B hamster strain; the abundance of Go alpha and Gi alpha 3 messenger RNAs did not change markedly. Moreover, the messenger RNA levels of Gs alpha and Gi alpha 2 decreased as the stage of cardiomyopathy progressed. Since G-proteins are linked to adenylate cyclase, these alterations of G-protein messenger RNA levels may be related to reduced contractility of cardiomyopathic heart.
Katoh
Y
Y
Third Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
Komuro
I
I
Takaku
F
F
Yamaguchi
H
H
Yazaki
Y
Y
D000818:Animals; D015152:Blotting, Northern; D009202:Cardiomyopathies / Q000378:metabolism*; D006224:Cricetinae; D019204:GTP-Binding Proteins / Q000235:genetics*; D006352:Heart Ventricles; D009206:Myocardium / Q000378:metabolism*; D009693:Nucleic Acid Hybridization; D012333:RNA, Messenger / Q000378:metabolism*; D012016:Reference Values
D012333:RNA, Messenger; D019204:GTP-Binding Proteins