Protein synthesis during right-ventricular hypertrophy after pulmonary-artery stenosis in the dog.
The rate of protein synthesis in the heart of normal dogs and those with pulmonary-artery stenosis was measured by a continuous intravenous infusion of [14C]tyrosine. The protein-synthesis rate of both ventricles was the same in normal dogs and averaged 7.5% per day. The right ventricle hypertrophied rapidly after the acute imposition of pulmonary-artery stenosis, the wet weight increasing by 84% after 24 days, with the rate of increase being most rapid over the first 5 days. The left ventricle remained largely unaffected and served as an internal control. During hypertrophy there was an increased incorporation of [14C]tyrosine into protein without a significant change in the specific radioactivity of free tyrosine in the ventricles. After 5 days of stenosis the synthesis rate of the total mixed proteins of the right ventricle had increased to 13.6% per day, compared with 6.2% in the control left ventricle. This increase in synthesis was reflected in both the myofibrillar and sarcoplasmic proteins. After 5 days the protein-synthesis rate decreased, but still remained significantly elevated above that in the control left ventricle by 24 days of stenosis.
D000818:Animals; D006332:Cardiomegaly / Q000209:etiology / Q000378:metabolism*; D004285:Dogs; D005260:Female; D008297:Male; D009124:Muscle Proteins / Q000096:biosynthesis*; D009929:Organ Size; D011666:Pulmonary Valve Stenosis / Q000150:complications / Q000378:metabolism*; D014443:Tyrosine / Q000097:blood
D009124:Muscle Proteins; D014443:Tyrosine