Abstract |
By using a novel approach for the study of the effects of pH variation in skinned myocardium, the present experiments were aimed to provide new insights into the mechanism of ischemia. Ca2+ sensitivity is decreased by acid pH, but the effect is more than double in cardiac myofilaments than that in fast-twitch skeletal muscle fibers. With the technique of troponin C exchange in myocytes, we find here that the effect of pH is the same with cardiac or skeletal troponin C. These results rule out a direct H+-Ca2+ competition on the Ca2+-binding sites of troponin C as a significant mechanism of ischemia. The findings provide conclusive evidence in favor of the idea that acidosis modulates the protein- protein interactions in the regulatory complex in cardiac muscle.
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Authors | J Gulati, A Babu |
Journal | FEBS letters
(FEBS Lett)
Vol. 245
Issue 1-2
Pg. 279-82
(Mar 13 1989)
ISSN: 0014-5793 [Print] England |
PMID | 2924925
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Troponin
- Troponin C
- Calcium
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Topics |
- Animals
- Calcium
(metabolism, pharmacology)
- Coronary Disease
(metabolism)
- Cricetinae
- Heart
(drug effects)
- Hydrogen-Ion Concentration
- Mesocricetus
- Myocardium
(metabolism, pathology)
- Sarcomeres
(pathology)
- Troponin
(metabolism)
- Troponin C
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