Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-27T23:25:30.988Z Has data issue: false hasContentIssue false

Sarcoplasmic Reticulum Calcium Release Channels in Ventricles of Older Adult Hamsters*

Published online by Cambridge University Press:  31 March 2010

Peter A. Nicholl
Affiliation:
Department of Pharmacology, Dalhousie University
Susan E. Howlett*
Affiliation:
Department of Pharmacology, Dalhousie University
*
Requests for offprints should be sent to: / Les demandes de tirés-à-part doivent être addressées à : S.E. Howlett, Ph.D., Department of Pharmacology, 5850 College St., Dalhousie University, Halifax, NS B3H 1X5. ([email protected])

Abstract

Whether the density of sarcoplasmic reticulum (SR) calcium release channels / ryanodine receptors in the heart declines with age is not clear. We investigated age-related changes in the density of «3H»-ryanodine receptors in crude ventricular homogenates, which contained all ligand binding sites in heart and in isolated junctional SR membranes. Experiments utilized young (120 days) and older adult (300 days) hamsters. «3H»-ryanodine binding site density did not change with age in crude homogenate preparations, although total heart protein concentration increased significantly with age. In contrast, the density of «3H»-ryanodine binding sites decreased markedly in heavy SR membranes purified from older hearts. These results show that demonstration of age-related changes in cardiac ryanodine receptor density depends upon the preparation used. Furthermore, the increase in total ventricular protein with age suggests that normalization of data by membrane protein should be used with caution in studies of aging heart.

Résumé

Il n/est pas certain que la densité des canaux calciques / récepteurs à la ryanodine du réticulum sarcoplasmique (RS) dans le muscle cardiaque diminue en fonction de l/âge. Nous avons analysé les changements liés à l/âge dans la densité des récepteurs à la «3H»-ryanodine dans des broyats ventriculaires grossiers contenant tous les sites de liaison des ligands dans le muscle cardiaque, ainsi que dans les membranes jonctionnelles isolées du RS. Des expériences ont été réalisées sur de jeunes hamsters (de 120 jours) et sur des hamsters adultes (de 300 jours). La densité des sites de liaison de la «3H»-ryanodine ne changeait pas dans les préparations de broyat grossier, mais la concentration totale des protéines cardiaques augmentait de façon significative en fonction de l/âge. Par contre, la densité des sites de liaison de la «3H»-ryanodine diminuait sensiblement dans les membranes lourdes purifiées du réticulum sarcoplasmique provenant de coeurs plus âgés. Ces résultats montrent que les démonstrations des changements liés à l/âge dans la densité des récepteurs à la ryanodine dans le muscle cardiaque dépendent du type de préparation utilisée. De plus, l/augmentation des protéines ventriculaires totales en fonction de l/âge suggère qu/il convient d/être prudent lorsqu/on procède à une normalisation des données en fonction des protéines de la membrane dans les études sur le vieillissement du muscle cardiaque.

Type
Articles
Copyright
Copyright © Canadian Association on Gerontology 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

*

The authors would like to thank H. Chan for excellent technical assistance. This study was supported by a grant from the Canadian Institutes of Health Research.

References

1.Lakatta, EG, Levy, D. Arterial and cardiac aging—major shareholders in cardiovascular disease enterprises: Part 1—aging arteries—a “set up” for vascular disease. Circulation 2003;107:139146.CrossRefGoogle Scholar
2.Laktta, EG. Arterial and cardiac aging—major shareholders in cardiovascular disease enterprises: Part 3—cellular and molecular clues to heart and arterial aging. Circulation 2003;107:490497.CrossRefGoogle Scholar
3.Lakatta, EG, Levy, D. Arterial and cardiac aging—major shareholders in cardiovascular disease enterprises: Part 2—the aging heart in health—links to heart disease. Circulation 2003;107:346354.CrossRefGoogle Scholar
4.Lakatta, EG, Sollott, SJ. Perspectives on mammalian cardiovascular aging: humans to molecules. Comp Biochem Physiol A Mol Integr Physiol 2002;132:699721.CrossRefGoogle ScholarPubMed
5.Bers, DM. Excitation-Contraction Coupling and Cardiac Contractile Force. 2nd ed.Dordrecht, The Netherlands: Kluwer Academic; 2001.CrossRefGoogle Scholar
6.Lehnart, SE, Wehrens, XH, Kushnir, A, Marks, AR. Cardiac ryanodine receptor function and regulation in heart disease. Ann N Y Acad Sci 2004;1015:144159.CrossRefGoogle ScholarPubMed
7.Cain, BS, Meldrum, DR, Joo, KS, Wang, JF, Meng, X, Cleveland, JC Jr. et al. . Human SERCA2a levels correlate inversely with age in senescent human myocardium. J Am Coll Cardiol 1998;32:458467.CrossRefGoogle ScholarPubMed
8.Froehlich, JP, Lakatta, EG, Beard, E, Spurgeon, HA, Weisfeldt, ML, Gerstenblith, G. Studies of sarcoplasmic reticulum function and contraction duration in young adult and aged rat myocardium. J Mol Cell Cardiol 1978;10:427438.CrossRefGoogle ScholarPubMed
9.Frolkis, VV, Frolkis, RA, Mkhitarian, LS, Fraifeld, VE. Age-dependent effects of ischemia and reperfusion on cardiac function and Ca2+ transport in myocardium. Gerontology 1991;37:233239.CrossRefGoogle ScholarPubMed
10.Heyliger, CE, Prakash, AR, McNeill, JH. Effect of calmodulin on sarcoplasmic reticular Ca2+ transport in the aging heart. Mol Cell Biochem 1989;85:7579.CrossRefGoogle ScholarPubMed
11.Lim, CC, Apstein, CS, Colucci, WS, Liao, R. Impaired cell shortening and relengthening with increased pacing frequency are intrinsic to the senescent mouse cardiomyocyte. J Mol Cell Cardiol 2000;32:20752082.CrossRefGoogle Scholar
12.Narayanan, N. Differential alterations in ATP-supported calcium transport activities of sarcoplasmic reticulum and sarcolemma of aging myocardium. Biochim Biophys Acta 1981;678:442459.CrossRefGoogle ScholarPubMed
13.Narayanan, N. Comparison of ATP-dependent calcium transport and calcium-activated ATPase activities of cardiac sarcoplasmic reticulum and sarcolemma from rats of various ages. Mech Ageing Dev 1987;38:127143.CrossRefGoogle ScholarPubMed
14.Taffet, GE, Tate, CA. Ca ATPase content is lower in cardiac sarcoplasmic reticulum isolated from old rats. Am J Physiol 1993;264:H1609H1614.Google Scholar
15.Xu, A, Narayanan, N. Effects of aging on sarcoplasmic reticulum Ca2+-cycling proteins and their phosphorylation in rat myocardium. Am J Physiol 1998;275:H2087H2094.Google ScholarPubMed
16.Gorza, L, Vettore, S, Tessaro, A, Sorrentino, V, Vitadello, M. Regional and age-related differences in mRNA composition of intracellular Ca2+ -release channels of rat cardiac myocytes. J Mol Cenll Cardiol 1997;29:10231036.CrossRefGoogle ScholarPubMed
17.Assayag, P, Charlemagne, D, Marty, I, de, Leiris J, Lompre, AM, Boucher, F et al. . Effects of sustained low-flow ischemia on myocardial function and calcium-regulating proteins in adult and senescent rat hearts. Cardiovasc Res 1998;38:169180.CrossRefGoogle ScholarPubMed
18.Barchi, RL, Weigele, JB, Chalikian, DM, Murphy, LE. Muscle surface membranes: preparative methods affect apparent chemical properties and neurotoxin binding. Biochim Biophys Acta 1979;550:5976.CrossRefGoogle ScholarPubMed
19.Lachnit, WG, Phillips, M, Gayman, KJ, Pessah, IN. Ryanodine and dihydropyridine binding patterns and ryanodine receptor mRNA levels in myopathic hamster heart. Am J Physiol 1994;267:H12051213.Google ScholarPubMed
20.Volpe, P, Damiani, E, Salviati, G and Margreth, A. Transitions in membrane composition during postnatal development of rabbit fast muscle. J Muscle Res Cell Motil 1982;3:213230.CrossRefGoogle ScholarPubMed
21.Canadian Council on Animal Care. Care and use of experimental animals «online». Ottawa: Canadian Council on Animal Care; 1984 (vol. 2); 1993 (vol. 1) «cited 2006 Jan 17». Available from: URL: http://www.ccac.ca/.Google Scholar
22.Anderson, K, Lai, FA, Liu, QY, Rousseau, E, Erickson, HP, Meissner, G. Structural and functional characterization of the purified cardiac ryanodine receptor-Ca2+ release channel complex. J Biol Chem 1989;264:13291335.CrossRefGoogle ScholarPubMed
23.Sapp, JL, Howlett, SE. Density of ryanodine receptors is increased in sarcoplasmic reticulum from prehypertrophic cardiomyopathic hamster heart. J Mol Cell Cardiol 1994;26:325334.CrossRefGoogle ScholarPubMed
24.Lowry, OH, Rosebrough, NJ, Farr, AL and Randall, RJ. Protein measurement with the Folin phenol reagent. J Biol Chem 1951;193:265275.CrossRefGoogle ScholarPubMed
25.Sachs, HG, Colgan, JA, Lazarus, ML. Ultrastructure of the aging myocardium: a morphometric approach. Am J Anat 1977;150:6371.CrossRefGoogle ScholarPubMed
26.Park, KS, Kim, TK, Kim, DH. Cyclosporin A treatment alters characteristics of Ca2+-release channel in cardiac sarcoplasmic reticulum. Am J Physiol 1999;276:H865H872.Google ScholarPubMed
27.De Blasi, A, Cotecchia, S, Mennini, T. Selective changes of receptor binding in brain regions of aged rats. Life Sci 1982;31:335340.CrossRefGoogle ScholarPubMed