Advertisement

Investigation into the positive inotropic effect of clondine in isolated hearts

  • A. Csongrady
  • W. Kobinger
Article

Summary

Clonidine in doses 2.5–40 μg injected into the aortic cannula of isolated, perfused hearts of guinea pigs produced an increase in contraction amplitude. This positive inotropic effect was not antagonised by infusions of doberol (10 μg/min), phentolamine (10 μg/min) or pheniramine (50 μg/min), it was antagonised by burimamide (30 μg/min), a histamine H2 receptor blocking agent. Clonidine showed some similarities to histamine such as parallel dose-response curves and during infusions of burimamide the curve of clonidine was shifted in a way which indicated competitive inhibition. It is suggested therefore that the action of clonidine is due to stimulation of histamine H2 receptors.

Key words

Clonidine Burimamide Positive Inotropic Action Histamine H2 Receptor 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Ash, H. O., Schild, A. S. F.: Receptors, mediating some actions of histamine. Brit J. Pharmacol. 27, 427 (1966)Google Scholar
  2. Black, J. W., Duncan, W. A. M., Durant, C. F., Ganellin, D. R., Parsons, E. M.: Definition and antagonism of histamine H2-receptors. Nature (Lond.) 236, 385 (1972)Google Scholar
  3. Hoefke, W., Kobinger, W.: Pharmakologische Wirkungen des 2-(2,6-Dichlorphenylamino)-2-Imidazolinhydrochlorids, einer neuen, antihypertensiven Substanz. Arzneimittel-Forsch. (Drug Res.) 16, 1038 (1966)Google Scholar
  4. James, T. N., Bear, E. S., Lang, K. F., Green, E. W.: Evidence for adrenergic alpha receptor depressant activity in the heart. Amer. J. Physiol. 215, 1366 (1968)Google Scholar
  5. Kaess, H., Mikulicz-Radecki, J. von: Der Einfluß von 2-(2,6-Dichlorphenylamino)-2-imidazolin-hydrochlorid (Catapresan) auf die Funktion von Magen und Pankreas. Europ. J. klin. Pharmacol. 3, 97 (1971)Google Scholar
  6. Kobinger, W.: Pharmacologic basis of the cardiovascular actions of clonidine. In: Hypertension: Mechanism and Management, ed. by G. Onesti, K. E. Kim, and J. H. Moyer. New York: Grune & Stratton 1973Google Scholar
  7. Kobinger, W., Walland, A.: Kreislaufuntersuchungen mit 2-(2,6-Dichlorphenylamino)-2-imidazolinhydrochlorid. Arzneimittel-Forsch. (Drug Res.) 17, 292 (1967)Google Scholar
  8. Langendorff, O.: Untersuchungen am überlebenden Säugetierherzen. Pflügers Arch. 61, 219 (1895)Google Scholar
  9. Mujic, M., Rossum, J. M. van: Comperative pharmacodynamics of sympathomimetic imidazolines; studies on intestinal smooth muscle of the rabbit and the cardiovascular system of the cat. Arch. int. Pharmacodyn. 155, 432 (1965)Google Scholar
  10. Pöch, G., Scholz, N., Kukovetz, W. R.: Inhibition of the cardiac effects of histamine on contraction and cyclic AMP by burimamide. Naunyn-Schmiedeberg's Arch. Pharmacol. 277, R 56 (1973)Google Scholar
  11. Rehbinder, D., Deckers, W.: Untersuchungen zur Pharmakokinetik und zum Metabolismus des 2-(2,6-Dichlorphenylamino)-2-imidazolinhydrochlorid (ST 155). Arzneimittel-Forsch. (Drug. Res.) 19, 169 (1969)Google Scholar
  12. Schild, H. O.: pA, a new scale for measurements of drug antagonism. Brit. J. Pharmacol. 2, 189 (1947)Google Scholar
  13. Trendelenburg, U.: The action of histamine and 5-hydroxytryptamine on isolated mammalian atria. J. Pharmacol. exp. Ther. 130, 450 (1960)Google Scholar
  14. Washizu, Y.: Differential effects of clonidine on guinea pig aterial and papillary muscles. Arch. int. Pharmacodyn. 196, 184 (1972)Google Scholar
  15. Walz, A., Zwieten, P. A. van: The influence of 2-(2,6-Dichlorphenylamino)-2-imidazoline hydrochloride (clonidine) and some related compounds on gastric secretion in the anaesthetized rat. Europ. J. Pharmacol. 10, 369 (1970)Google Scholar

Copyright information

© Springer-Verlag 1974

Authors and Affiliations

  • A. Csongrady
    • 1
  • W. Kobinger
    • 1
  1. 1.Department of PharmacologyArzneimittelforschung GmbHWienAustria

Personalised recommendations