Abstract
We describe the changes in proportions of myofibrillar proteins elicited by chronic congestive heart failure in the costal diaphragm (DIA) of humans using one and two-dimensional electrophoretic techniques. Three myosin heavy chain (MHC) isoforms were found in the DIA from control subjects: slow MHC I (43 ± S.E. 2%), fast MHC IIa (41 ± 2%) and fast MHC IIb (17 ± 1%). In heart failure DIA, the percentage of MHC I was increased to 57 ± 2%, while that of MHC IIb was decreased to 8 ± 2 (P < 0.001 for both cases). Similarly, this DIA had higher molar ratios (%) of the slow myosin light chain isoforms (i.e. 1sa, 1sb, and 2s), and lower molar ratios of the fast isoforms (i.e. If, 2f, and 3f) than control DIA. Heart failure DIA also contained lower proportions of both α-tropomyosin and fast isoforms of troponin-T, I and C than control DIA. These results indicate that heart failure elicits fast-to-slow transformations of both myosin and regulatory proteins of human costal DIA. These changes can be viewed as an increase in slow-twitch characteristics of the DIA and differ from the adaptations elicited by heart failure in limb muscles.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2537-2541 |
| Number of pages | 5 |
| Journal | Journal of Molecular and Cellular Cardiology |
| Volume | 28 |
| Issue number | 12 |
| DOIs | |
| State | Published - Dec 1996 |
| Externally published | Yes |
Keywords
- Heart failure
- Human diaphragm
- Myofibrillar proteins
- Myosin heavy chain isoforms
- Troponin-tropomyosin regulatory complex
ASJC Scopus subject areas
- Molecular Biology
- Cardiology and Cardiovascular Medicine