Abstract
Dog erythrocytes (RBC) have a system for passive Ca and Na movements that resembles the Ca-Na exchanger first described in cardiac muscle. Amrinone, a new cardiotonic drug active in humans with congestive heart failure, is shown to stimulate net Ca uptake by dog RBC. Amrinone's action is on Ca influx rather than efflux. The influence of Amrinone on Ca uptake is enhanced when the cells are placed in low Na media; raising external Na or lowering intracellular Na both abolish the effect of the drug. The data suggest that amrinone potentiates passive Ca entry into the cells by a Na-dependent pathway. If Ca moves through myocardial sarcolemma as it does through dog RBC membranes, then the inotropic action of amrinone can be explained on the basis that the drug increases intracellular Ca levels.
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Selected References
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- Alousi A. A., Farah A. E., Lesher G. Y., Opalka C. J., Jr Cardiotonic activity of amrinone--Win 40680 [5-amino-3,4'-bipyridine-6(1H)-one]. Circ Res. 1979 Nov;45(5):666–677. doi: 10.1161/01.res.45.5.666. [DOI] [PubMed] [Google Scholar]
- Baker P. F., Blaustein M. P., Hodgkin A. L., Steinhardt R. A. The influence of calcium on sodium efflux in squid axons. J Physiol. 1969 Feb;200(2):431–458. doi: 10.1113/jphysiol.1969.sp008702. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Benotti J. R., Grossman W., Braunwald E., Davolos D. D., Alousi A. A. Hemodynamic assessment of amrinone. A new inotropic agent. N Engl J Med. 1978 Dec 21;299(25):1373–1377. doi: 10.1056/NEJM197812212992501. [DOI] [PubMed] [Google Scholar]
- Farah A. E., Alousi A. A. New cardiotonic agents: a search for digitalis substitute. Life Sci. 1978 Apr 3;22(13-15):1139–1147. doi: 10.1016/0024-3205(78)90083-8. [DOI] [PubMed] [Google Scholar]
- Katz A. M. A new inotropic drug: its promise and a caution. N Engl J Med. 1978 Dec 21;299(25):1409–1410. doi: 10.1056/NEJM197812212992508. [DOI] [PubMed] [Google Scholar]
- NIEDERGERKE R. Calcium and the activation of contraction. Experientia. 1959 Apr 15;15(4):128–130. doi: 10.1007/BF02165519. [DOI] [PubMed] [Google Scholar]
- OMACHI A., MARKEL R. P., HEGARTY H. Ca45 uptake by dog erythrocytes suspended in sodium and potassium chloride solutions. J Cell Comp Physiol. 1961 Apr;57:95–100. doi: 10.1002/jcp.1030570206. [DOI] [PubMed] [Google Scholar]
- Parker J. C. Active and passive Ca movements in dog red blood cells and resealed ghosts. Am J Physiol. 1979 Jul;237(1):C10–C16. doi: 10.1152/ajpcell.1979.237.1.C10. [DOI] [PubMed] [Google Scholar]
- Parker J. C., Castranova V., Goldfinger J. M. Dog red blood cells: Na and K diffusion potentials with extracellular ATP. J Gen Physiol. 1977 Apr;69(4):417–430. doi: 10.1085/jgp.69.4.417. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Parker J. C. Dog red blood cells. Adjustment of density in vivo. J Gen Physiol. 1973 Feb;61(2):146–157. doi: 10.1085/jgp.61.2.146. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Parker J. C. Dog red blood cells. Adjustment of salt and water content in vitro. J Gen Physiol. 1973 Aug;62(2):147–156. doi: 10.1085/jgp.62.2.147. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Parker J. C., Gitelman H. J., Glosson P. S., Leonard D. L. Role of calcium in volume regulation by dog red blood cells. J Gen Physiol. 1975 Jan;65(1):84–96. doi: 10.1085/jgp.65.1.84. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Parker J. C., Snow R. L. Influence of external ATP on permeability and metabolism of dog red blood cells. Am J Physiol. 1972 Oct;223(4):888–893. doi: 10.1152/ajplegacy.1972.223.4.888. [DOI] [PubMed] [Google Scholar]
- Parker J. C. Sodium and calcium movements in dog red blood cells. J Gen Physiol. 1978 Jan;71(1):1–17. doi: 10.1085/jgp.71.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pine M. B., Bing O. H., Weintraub R., Abelmann W. H. Dissociation of cell volume regulation and sodium-potassium exchange pump activity in dog myocardium in vitro. J Mol Cell Cardiol. 1979 Jun;11(6):585–590. doi: 10.1016/0022-2828(79)90432-2. [DOI] [PubMed] [Google Scholar]
- Pitts B. J. Stoichiometry of sodium-calcium exchange in cardiac sarcolemmal vesicles. Coupling to the sodium pump. J Biol Chem. 1979 Jul 25;254(14):6232–6235. [PubMed] [Google Scholar]
- Reuter H., Seitz N. The dependence of calcium efflux from cardiac muscle on temperature and external ion composition. J Physiol. 1968 Mar;195(2):451–470. doi: 10.1113/jphysiol.1968.sp008467. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SCHATZMANN H. J. Herzglykoside als Hemmstoffe für den aktiven Kalium- und Natriumtransport durch die Erythrocytenmembran. Helv Physiol Pharmacol Acta. 1953;11(4):346–354. [PubMed] [Google Scholar]
- WINEGRAD S. The possible role of calcium in excitation-contraction coupling of heart muscle. Circulation. 1961;24:523–529. doi: 10.1161/01.cir.24.2.523. [DOI] [PubMed] [Google Scholar]
