Abstract
Cardiac work is a major determinant of heart size and growth. Heterotopic cardiac isografts are hemodynamically unloaded and undergo atrophy. To determine the molecular changes that occur as a result of hemodynamic unloading, we have studied the rate of synthesis of total cardiac proteins and myosin heavy chain (MHC) and the expression of the myosin heavy chain gene as reflected in the messenger RNA levels for alpha- and beta-MHC isoforms. 72 h after transplantation there is a significant decrease in left ventricular size accompanied by a 27% decrease in the rate of total cardiac protein synthesis and a 53% decrease in the rate of myosin heavy chain synthesis. In contrast to isografts 14 d after transplantation which have a decrease in protein synthetic capacity, simultaneous measurements of 18S ribosomal RNA and myosin messenger RNA suggest that after 3 d the decrease in synthesis is due to a change in the efficiency of protein translation. While the working in situ heart expresses primarily alpha-MHC mRNA (97%) hemodynamic unloading leads to a 43% decrease in alpha-MHC mRNA concentration and the de novo expression of the beta-MHC mRNA. Total MHC mRNA (alpha plus beta) concentration analyzed by a quantitative S1 nuclease protection assay was similar in the two groups of hearts. Thus, in association with hemodynamic unloading there are changes in cardiac myosin heavy chain content as a result of both gene transcription and protein translation mechanisms.
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- Advani S. V., Geenen D., Malhotra A., Factor S. M., Scheuer J. Swimming causes myosin adaptations in the rat cardiac isograft. Circ Res. 1990 Sep;67(3):780–783. doi: 10.1161/01.res.67.3.780. [DOI] [PubMed] [Google Scholar]
- Cesarone C. F., Bolognesi C., Santi L. Improved microfluorometric DNA determination in biological material using 33258 Hoechst. Anal Biochem. 1979 Nov 15;100(1):188–197. doi: 10.1016/0003-2697(79)90131-3. [DOI] [PubMed] [Google Scholar]
- Chomczynski P., Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal Biochem. 1987 Apr;162(1):156–159. doi: 10.1006/abio.1987.9999. [DOI] [PubMed] [Google Scholar]
- Cooper G., 4th, Kent R. L., Uboh C. E., Thompson E. W., Marino T. A. Hemodynamic versus adrenergic control of cat right ventricular hypertrophy. J Clin Invest. 1985 May;75(5):1403–1414. doi: 10.1172/JCI111842. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dillmann W. H., Barrieux A., Neeley W. E., Contreras P. Influence of thyroid hormone on the in vitro translational activity of specific mRNAs in the rat heart. J Biol Chem. 1983 Jun 25;258(12):7738–7745. [PubMed] [Google Scholar]
- Dillmann W. H. Diabetes mellitus induces changes in cardiac myosin of the rat. Diabetes. 1980 Jul;29(7):579–582. doi: 10.2337/diab.29.7.579. [DOI] [PubMed] [Google Scholar]
- Everett A. W., Prior G., Zak R. Equilibration of leucine between the plasma compartment and leucyl-tRNA in the heart, and turnover of cardiac myosin heavy chain. Biochem J. 1981 Jan 15;194(1):365–368. doi: 10.1042/bj1940365. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Everett A. W., Sinha A. M., Umeda P. K., Jakovcic S., Rabinowitz M., Zak R. Regulation of myosin synthesis by thyroid hormone: relative change in the alpha- and beta-myosin heavy chain mRNA levels in rabbit heart. Biochemistry. 1984 Apr 10;23(8):1596–1599. doi: 10.1021/bi00303a002. [DOI] [PubMed] [Google Scholar]
- Gustafson T. A., Bahl J. J., Markham B. E., Roeske W. R., Morkin E. Hormonal regulation of myosin heavy chain and alpha-actin gene expression in cultured fetal rat heart myocytes. J Biol Chem. 1987 Sep 25;262(27):13316–13322. [PubMed] [Google Scholar]
- Hoh J. F., McGrath P. A., Hale P. T. Electrophoretic analysis of multiple forms of rat cardiac myosin: effects of hypophysectomy and thyroxine replacement. J Mol Cell Cardiol. 1978 Nov;10(11):1053–1076. doi: 10.1016/0022-2828(78)90401-7. [DOI] [PubMed] [Google Scholar]
- Izumo S., Lompré A. M., Matsuoka R., Koren G., Schwartz K., Nadal-Ginard B., Mahdavi V. Myosin heavy chain messenger RNA and protein isoform transitions during cardiac hypertrophy. Interaction between hemodynamic and thyroid hormone-induced signals. J Clin Invest. 1987 Mar;79(3):970–977. doi: 10.1172/JCI112908. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Klein I., Hong C. Effects of thyroid hormone on cardiac size and myosin content of the heterotopically transplanted rat heart. J Clin Invest. 1986 May;77(5):1694–1698. doi: 10.1172/JCI112488. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Klein I., Samarel A. M., Welikson R., Hong C. Heterotopic cardiac transplantation decreases the capacity for rat myocardial protein synthesis. Circ Res. 1991 Apr;68(4):1100–1107. doi: 10.1161/01.res.68.4.1100. [DOI] [PubMed] [Google Scholar]
- Korecky B., Ganguly P. K., Elimban V., Dhalla N. S. Muscle mechanics and Ca2+ transport in atrophic heart transplants in rat. Am J Physiol. 1986 Nov;251(5 Pt 2):H941–H948. doi: 10.1152/ajpheart.1986.251.5.H941. [DOI] [PubMed] [Google Scholar]
- Kraft R., Bravo-Zehnder M., Taylor D. A., Leinwand L. A. Complete nucleotide sequence of full length cDNA for rat beta cardiac myosin heavy chain. Nucleic Acids Res. 1989 Sep 25;17(18):7529–7530. doi: 10.1093/nar/17.18.7529. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
- McDermott P. J., Morgan H. E. Contraction modulates the capacity for protein synthesis during growth of neonatal heart cells in culture. Circ Res. 1989 Mar;64(3):542–553. doi: 10.1161/01.res.64.3.542. [DOI] [PubMed] [Google Scholar]
- McDermott P., Daood M., Klein I. Contraction regulates myosin synthesis and myosin content of cultured heart cells. Am J Physiol. 1985 Oct;249(4 Pt 2):H763–H769. doi: 10.1152/ajpheart.1985.249.4.H763. [DOI] [PubMed] [Google Scholar]
- McDermott P., Daood M., Klein I. Measurement of myosin adenosinetriphosphatase and myosin content in cultured heart cells. Arch Biochem Biophys. 1985 Jul;240(1):312–318. doi: 10.1016/0003-9861(85)90036-0. [DOI] [PubMed] [Google Scholar]
- Mercadier J. J., Lompré A. M., Wisnewsky C., Samuel J. L., Bercovici J., Swynghedauw B., Schwartz K. Myosin isoenzyme changes in several models of rat cardiac hypertrophy. Circ Res. 1981 Aug;49(2):525–532. doi: 10.1161/01.res.49.2.525. [DOI] [PubMed] [Google Scholar]
- Morgan H. E., Baker K. M. Cardiac hypertrophy. Mechanical, neural, and endocrine dependence. Circulation. 1991 Jan;83(1):13–25. doi: 10.1161/01.cir.83.1.13. [DOI] [PubMed] [Google Scholar]
- Morgan H. E., Earl D. C., Broadus A., Wolpert E. B., Giger K. E., Jefferson L. S. Regulation of protein synthesis in heart muscle. I. Effect of amino acid levels on protein synthesis. J Biol Chem. 1971 Apr 10;246(7):2152–2162. [PubMed] [Google Scholar]
- Morgan H. E., Gordon E. E., Kira Y., Chua H. L., Russo L. A., Peterson C. J., McDermott P. J., Watson P. A. Biochemical mechanisms of cardiac hypertrophy. Annu Rev Physiol. 1987;49:533–543. doi: 10.1146/annurev.ph.49.030187.002533. [DOI] [PubMed] [Google Scholar]
- Nadal-Ginard B., Mahdavi V. Molecular basis of cardiac performance. Plasticity of the myocardium generated through protein isoform switches. J Clin Invest. 1989 Dec;84(6):1693–1700. doi: 10.1172/JCI114351. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nagai R., Pritzl N., Low R. B., Stirewalt W. S., Zak R., Alpert N. R., Litten R. Z. Myosin isozyme synthesis and mRNA levels in pressure-overloaded rabbit hearts. Circ Res. 1987 May;60(5):692–699. doi: 10.1161/01.res.60.5.692. [DOI] [PubMed] [Google Scholar]
- Nair K. G., Cutilletta A. F., Zak R., Koide T., Rabinowitz M. Biochemical correlates of cardiac hypertrophy. I. Experimental model; changes in heart weight, RNA content, and nuclear RNA polymerase activity. Circ Res. 1968 Sep;23(3):451–462. doi: 10.1161/01.res.23.3.451. [DOI] [PubMed] [Google Scholar]
- Ono K., Lindsey E. S. Improved technique of heart transplantation in rats. J Thorac Cardiovasc Surg. 1969 Feb;57(2):225–229. [PubMed] [Google Scholar]
- Paynton B. V., Rempel R., Bachvarova R. Changes in state of adenylation and time course of degradation of maternal mRNAs during oocyte maturation and early embryonic development in the mouse. Dev Biol. 1988 Oct;129(2):304–314. doi: 10.1016/0012-1606(88)90377-6. [DOI] [PubMed] [Google Scholar]
- Samarel A. M. In vivo measurements of protein turnover during muscle growth and atrophy. FASEB J. 1991 Apr;5(7):2020–2028. doi: 10.1096/fasebj.5.7.2010055. [DOI] [PubMed] [Google Scholar]
- Samarel A. M., Parmacek M. S., Magid N. M., Decker R. S., Lesch M. Protein synthesis and degradation during starvation-induced cardiac atrophy in rabbits. Circ Res. 1987 Jun;60(6):933–941. doi: 10.1161/01.res.60.6.933. [DOI] [PubMed] [Google Scholar]
- Schneider M. D., Parker T. G. Cardiac myocytes as targets for the action of peptide growth factors. Circulation. 1990 May;81(5):1443–1456. doi: 10.1161/01.cir.81.5.1443. [DOI] [PubMed] [Google Scholar]
- Schreiber S. S., Evans C. D., Oratz M., Rothschild M. A. Protein synthesis and degradation in cardiac stress. Circ Res. 1981 May;48(5):601–611. doi: 10.1161/01.res.48.5.601. [DOI] [PubMed] [Google Scholar]
- Siehl D., Chua B. H., Lautensack-Belser N., Morgan H. E. Faster protein and ribosome synthesis in thyroxine-induced hypertrophy of rat heart. Am J Physiol. 1985 Mar;248(3 Pt 1):C309–C319. doi: 10.1152/ajpcell.1985.248.3.C309. [DOI] [PubMed] [Google Scholar]
- Smith J. A., Mottram P. L., Mirisklavos A., Mason A., Dumble L. J., Clunie G. J. The effect of operative ischemia in murine cardiac transplantation: isograft control studies. Surgery. 1987 Jan;101(1):86–90. [PubMed] [Google Scholar]
- Waspe L. E., Ordahl C. P., Simpson P. C. The cardiac beta-myosin heavy chain isogene is induced selectively in alpha 1-adrenergic receptor-stimulated hypertrophy of cultured rat heart myocytes. J Clin Invest. 1990 Apr;85(4):1206–1214. doi: 10.1172/JCI114554. [DOI] [PMC free article] [PubMed] [Google Scholar]


