Increased Synthesis of the Phosphorylated Form of the Myosin Light Chains in Cardiac Hypertrophy in the Rat
The incorporation rate of [3H]leucine into cardiac myosin subunits was studied in rat hearts undergoing hypertrophy secondary to constriction of the ascending aorta. Cardiac myosin was prepared by a modified Shiverick’s method on the second and fourth day after constriction. Myosin light chains were separated by urea and subjected to two-dimensional electrophoresis. Incorporation of [3H]leucine was determined in electrophoretically separated heavy and light chains by the method of Martin et al. (11). It was found that the incorporation rate of [3H]leucine into the phosphorylated form of the myosin light chain 2 is significantly increased in hypertrophic hearts as compared to sham animals.
KeywordsLight Chain Myosin Light Chain Phosphorylated Form Specific Radioactivity Myosin Light Chain Kinase
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