The correlation between expression of apoptosis-related proteins and myocardial functional reserve evaluated by dobutamine stress echocardiography in patients with dilated cardiomyopathy.
The relation between myocardial functional changes and the apoptosis-related proteins in patients with dilated cardiomyopathy (DCM) has not yet been reported. The purpose of this study was to assess this issue through the use of dobutamine stress echocardiography. A total of 81 segments of left ventricles (from 6 patients with DCM) were collected in this study. Segments from another 5 patients who had died of noncardiac causes were used as the control. Apoptosis-related proteins (bax, bcl-2, and p53) and apoptosis were evaluated in these segments by immunocytochemical stain and terminal deoxynucleotidyl transferase-mediated DNA nick end-labeling assay. There were 26 segments with dobutamine-induced contractile reserve. There were significant differences in numbers of segments with overexpression of bcl-2 and bax in the study and control groups. However, p53 was not found in either group. The total terminal deoxynucleotidyl transferase-mediated DNA nick end-labeling-positive nuclei in explanted hearts of DCM was 0.73%. The myocardial contractile reserve was inversely associated with an overexpression of bcl-2 (P <.01) rather than bax. In conclusion, the expression of bax and bcl-2 proteins in patients with DCM is enhanced and independent of p53. Loss of contractile reserve is associated with overexpression of bcl-2 protein in failing myocardium.
Ho
Yi-Lwun
YL
Department of Internal Medicine, National Taiwan University Hospital, Taipei.
Chen
Chi-Long
CL
Hsu
Ron-Bin
RB
Lin
Lung-Chun
LC
Huang
Por-Jau
PJ
D000328:Adult; D017209:Apoptosis / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D002311:Cardiomyopathy, Dilated / Q000378:metabolism* / Q000503:physiopathology*; D002316:Cardiotonic Agents / Q000494:pharmacology; D003864:Depression, Chemical; D004280:Dobutamine / Q000494:pharmacology; D025401:Echocardiography, Stress; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006346:Heart Septum / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D006352:Heart Ventricles / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D020287:In Situ Nick-End Labeling; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects / Q000502:physiology*; D009206:Myocardium / Q000166:cytology / Q000378:metabolism* / Q000473:pathology; D032383:Myocytes, Cardiac / Q000378:metabolism / Q000473:pathology; D011446:Prospective Studies; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D013223:Statistics as Topic; D013318:Stroke Volume / Q000502:physiology; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis; D051028:bcl-2-Associated X Protein
C494826:BAX protein, human; D002316:Cardiotonic Agents; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D004280:Dobutamine