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Updated: May 27, 2026

Assessment of Sarcoplasmic Reticulum Calcium Reserve and Intracellular Diastolic Calcium Removal in Isolated Ventricular Cardiomyocytes
Published on: September 18, 2017
Effect of prolonged fasting upon the calcium activated sarcoplasmic factor of rabbit skeletal muscle
1Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824, USA.
Abstract:
Adult male New Zealand rabbits were subjected to a 28-day fast (food deprivation). Various blood biochemical parameters, as well as organ and individual skeletal muscle (semitendinosus and longissimus dorsi) weights, were determined. Additionally, the effect of fasting upon individual skeletal muscle functions was assessed. The calcium activated sarcoplasmic factor (CASF) isolated from the fasted rabbits was compared with the same enzyme isolated from ad lib fed rabbits. The fasted rabbits yielded greater amounts of CASF of a slightly higher specific activity than the same enzyme derived from ad lib fed rabbits. However, the enzymes from both treatments exhibited similar activities on intact myofibrils, as demonstrated by phase contrast microscopy and SDS-polyacrylamide gel electrophoresis.
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