Skeletal and smooth muscle alpha-actin mRNA in endomyocardial biopsy samples of dilated cardiomyopathy patients.
Skeletal or smooth muscle alpha-actin isoform is reexpressed in hypertrophied or failing heart in experimental animals, however, it has been unknown whether there is a switching of these genes in the human heart. In this study, we assessed alpha-actin isoform mRNA in biopsied specimens from the left ventricle of patients with dilated cardiomyopathy (DCM). The biopsy was performed in 21 patients (DCM; 16, normal; 5). Skeletal and smooth muscle alpha-actin mRNA levels were assessed by quantitative reverse transcriptase-polymerase chain reaction using a synthetic RNA as internal control. The level of both alpha-actin mRNAs correlated well with the mean cardiomyocyte diameter as an index of cardiac hypertrophy. Further, there was a clear correlation between the expression of skeletal alpha-actin mRNA or smooth muscle alpha-actin mRNA and the ejection fraction. These results suggested that mRNAs for skeletal and smooth muscle alpha-actin isoforms are increased in the hypertrophic and/or failing heart. These mRNAs may be an useful marker for the pathological state of cardiomyopathy.
Adachi
S
S
Second Department of Internal Medicine, Tokyo Medical and Dental University, Japan.
Ito
H
H
Tamamori
M
M
Tanaka
M
M
Marumo
F
F
Hiroe
M
M
D000199:Actins / Q000096:biosynthesis*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002311:Cardiomyopathy, Dilated / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism; D009130:Muscle, Smooth / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis*
D000199:Actins; D012333:RNA, Messenger