Summary
In isolated spontaneously beating right ventricular strips and right atrial preparations of guinea pigs adenosine was found to exert a concentration-dependent suppressing effect on the pacemaker activity. Responsiveness to adenosine was approximately 30-fold higher in ventricular than in atrial preparations. A decrease in the rate of slow diastolic (phase 4) depolarization of Purkinje and sinoatrial nodal fibers proved to be a major determinant of the adenosine-induced alteration in pacemaker activity. It is suggested that adenosine might exert its depressant effect on ventricular automaticity via direct excitation of purine receptors located in the specialized pacemaker fibres of the ventricular tissue.
Similar content being viewed by others
References
Chiba, S.: Potentiation of the negative chronotropic and inotropic effects of adenosine by dipyridamole. Tohoku J. Exp. Med. 114, 45–48 (1974)
Chiba, S., Hashimoto, K.: Differences in chronotropic and dromotropic responses of the SA and AV nodes to adenosine and acetylcholine. Jap. J. Pharmacol. 22, 273–274 (1972)
Chiba, S., Himori, N.: Different inotropic responses to adenosine on the atrial and ventricular muscle of the dog heart. Jap. J. Pharmacol. 25, 489–491 (1975)
De Gubareff, T., Sleator, W.: Effects of caffeine on mammalian atrial muscle, and its interaction with adenosine and calcium. J. Pharmacol. Exp. Ther. 148, 202–214 (1965)
Drury, A. N., Szent-Györgyi, A.: The physiological activity of adenine compounds with especial reference to their action upon the mammalian heart. J. Physiology (Lond.) 68, 213–237 (1929)
James, T. N.: The chronotropic action of ATP and related compounds studied by direct perfusion of the sinus node. J. Pharmacol. Exp. Ther. 149, 233–247 (1965)
Papp, J. Gy., Vaughan Williams, E. M.: A comparison of the antiarrhythmic actions of I.C.I. 50172 and-/-/-propranolol and their effects on intracellular cardiac action potentials and other features of cardiac function. Br. J. Pharmacol. 37, 391–399 (1969a)
Papp, J. Gy., Vaughan Williams, E. M.: The effect of bretylium on intracellular cardiac action potentials in relation to its antiarrhythmic and local anaesthetic activity. Br. J. Pharmacol. 37, 380–390 (1969b)
Schöndorf, J., Rummel, W., Pfleger, K.: Dosis-Wirkungs-Beziehungen zwischen Koronardurchfluß und Herzfrequenz für Adenosin. Experientia 25, 44–45 (1969)
Szekeres, L., Vaughan Williams, E. M.: Antifibrillatory action. J. Physiol. (Lond.) 160, 470–482 (1962)
Szentmiklósi, A. J., Szegi, J., Németh, M., Papp, J. Gy., Szekeres, L.: Does adenosine exert any effect on heart ventricle? Abstracts Book of the Seventh International Congress of Pharmacology, p. 981. Paris 1978
Szentmiklósi, A. J., Németh, M., Szegi, J., Papp, J. Gy., Szekeres, L.: On the possible role of adenosine in the hypoxia-induced alterations of the electrical and mechanical activity of the atrial myocardium. Arch. Int. Pharmacodyn. Ther. 238, 283–295 (1979)
Urthaler, F., James, T. N.: Effects of adenosine and ATP on AV conduction and AV junctional rhythm. J. Lab. Clin. Med. 79, 96–105 (1972)
Versprille, A.: The chronotropic effect of adenine-and hypoxanthine derivatives on isolated rat hearts before and after removing the sino-atrial node. Pflügers Arch. 291, 261–267 (1966)
Author information
Authors and Affiliations
Additional information
This work was supported by the Scientific Research Council, Ministry of Public Health, Hungary, Grant No. 2-06-0101-02-2/Sz
Rights and permissions
About this article
Cite this article
Szentmiklósi, A.J., Németh, M., Szegi, J. et al. Effect of adenosine on sinoatrial and ventricular automaticity of the guinea pig. Naunyn-Schmiedeberg's Arch. Pharmacol. 311, 147–149 (1980). https://doi.org/10.1007/BF00510253
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00510253