Article: Effect of propranolol upon protein and proteolytic synthesis activity in hypertrophic myocardium

The aim of the study was to investigate the effect of propranolol upon protein synthesis and degradation processes in cell-free subfractions of rat myocardium in experimental cardiac hypertrophy induced by aortic stenosis. It was found that hypertrophy stimulates incorporation of 3H-amino acids by the postmitochondrial supernatant (PMS) by 17 +/- 4% (mean +/- SE). Propranolol 10 6M inhibited protein synthesis in the control and experimental groups by 37 +/- 5% and 34 +/- 7%, respectively. At a concentration of 5 X 10 6M, propranolol-induced inhibition in each group was 74 +/- 4% and 58 +/- 5%, respectively. The activity of neutral proteases in PMS of hypertrophic hearts increased up to 255 +/- 29 IU in comparison to 154 +/- 10 IU in controls; in the cytosol it was unchanged. Propranolol had no effect upon the activity of proteases in both fractions. Activity of calcium-activated neutral proteases (CANP) remained at the same level in control and hypertrophic hearts and was unaffected by propranolol.

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References

1.

Croxson R, Khanna P, Raphael M, STEINER R, Oakley C, Goodwin J . Cardioselective beta blockade in hypertrophic cardiomyopathy. Acta Cardiol. 1972; :Suppl 15:263-7. DOI: 10.1016/0002-9149(70)90559-x. View

2.

Hubner P, Ziady G, Lane G, Hardarson T, SCALES B, Oakley C . Double-blind trial of propranolol and practolol in hypertrophic cardiomyopathy. Br Heart J. 1973; 35(11):1116-23. PMC: 458765. DOI: 10.1136/hrt.35.11.1116. View

3.

Bourmayan C, Razavi A, Fournier C, Dussaule J, BARAGAN J, GERBAUX A . Effect of propranolol on left ventricular relaxation in hypertrophic cardiomyopathy: an echographic study. Am Heart J. 1985; 109(6):1311-6. DOI: 10.1016/0002-8703(85)90357-6. View

4.

Reddy M, Rabinowitz M, Zak R . Stringent requirement for Ca2+ in the removal of Z-lines and alpha-actinin from isolated myofibrils by Ca2+-activated neutral proteinase. Biochem J. 1983; 209(3):635-41. PMC: 1154140. DOI: 10.1042/bj2090635. View

5.

Swanton R, Brooksby I, Jenkins B, Webb-Peploe M . Hemodynamic studies of beta blockade in hypertrophic obstructive cardiomyopathy. Eur J Cardiol. 1977; 5(4):327-41. View

6.

Dayton W, Schollmeyer J, Lepley R, Cortes L . A calcium-activated protease possibly involved in myofibrillar protein turnover. Isolation of a low-calcium-requiring form of the protease. Biochim Biophys Acta. 1981; 659(1):48-61. DOI: 10.1016/0005-2744(81)90270-9. View

7.

Nosek T, Crosland M . Calcium-dependent proteolysis in neural tissue is activated at physiologic intracellular Ca2+ levels and inhibited by some anticonvulsants. J Neurobiol. 1983; 14(1):9-16. DOI: 10.1002/neu.480140103. View

8.

Albin R, Dowell R, Zak R, Rabinowitz M . Synthesis and degradation of mitochondrial components in hypertrophied rat heart. Biochem J. 1973; 136(3):629-37. PMC: 1165998. DOI: 10.1042/bj1360629. View

9.

Etlinger J, Speiser S, Wajnberg E, Glucksman M . ATP-dependent proteolysis in erythroid and muscle cells. Acta Biol Med Ger. 1981; 40(10-11):1285-91. View

10.

Conde R, SCORNIK O . Role of protein degradation in the growth of livers after a nutritional shift. Biochem J. 1976; 158(2):385-90. PMC: 1163981. DOI: 10.1042/bj1580385. View

11.

Tolnai S . Purification and some characteristics of a Ca2+-activated proteolytic enzyme from beef cardiac muscle. Can J Biochem. 1981; 59(4):242-9. DOI: 10.1139/o81-033. View

Effect of Propranolol Upon Protein and Proteolytic Synthesis Activity in Hypertrophic Myocardium