Abstract
Hearts isolated from 12-mo non-insulin-dependent diabetic rats exhibited reduced rates of contractility and relaxation. Associated with the abnormality in contractility was a redistribution in myosin isozyme content to the least active V3 form. Defects in myocardial relaxation also occurred concomitantly with impaired handling of calcium. Total tissue calcium content rose 35% in the diabetic hearts. At the same time, the activity of the pump responsible for maintaining normal cytoplasmic calcium levels was reduced. At a free calcium concentration of 2.0 μM, the rates of sarcoplasmic reticular calcium uptake and adenosinetriphosphatase activity of the diabetic hearts were decreased ~30%. Diastolic ventricular stiffness increased dramatically. The net result of these abnormalities in calcium metabolism is a significant impairment in mechanical performance of the diabetic heart.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 19/1 |
| Journal | American Journal of Physiology - Endocrinology and Metabolism |
| Volume | 256 |
| Issue number | 1 |
| State | Published - 1989 |
| Externally published | Yes |
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism
- Physiology
- Physiology (medical)
