Naunyn-Schmiedeberg's Archives of Pharmacology

, Volume 320, Issue 3, pp 240–245 | Cite as

β-Adrenoceptor ligand binding and supersensitivity to isoprenaline of ventricular muscle after chronic reserpine pretreatment

  • Mark H. Hawthorn
  • Kenneth J. Broadley
Article

Summary

  1. 1.

    Isolate papillary muscles from guinea-pig hearts were paced at a constant frequency and isometric contractions recorded.

     
  2. 2.

    Guinea-pigs were either untreated or pretreated with reserpine. Three pretreatment schedules were used; a) 0.5 mg kg−1 i.p. at 24h, b) 5.0 mg kg−1 at 72h and 3.0 mg kg−1 at 48 and 24 h, or c) 0.1 mg kg−1 daily for 7 days.

     
  3. 3.

    Cumulative concentration-response curves for the isoprenaline-induced increases in tension were obtained. The geometric mean EC50 values after the 3 and 7 day reserpine pretreatment schedules were significantly (P<0.05) less than for untreated guinea-pigs indicating a supersensitivity.

     
  4. 4.

    EC50 values for the positive inotropic inotropic responses to histamine and calcium in papillary muscles from reserpine-pretreated guinea-pigs did not differ significantly (P<0.05) from those from untreated animals. This suggests that the supersensitivity to isoprenaline is β-adrenoceptor specific.

     
  5. 5.

    Membrane fractions were prepared from the ventricles of the untreated and reserpine-pretreated guinea-pigs from which papillary muscles had been removed. Binding of [3H]-dihydroalprenolol ([3H]-DHA) to β-adrenoceptors of these membranes was determined. Equilibrium dissociation constants (KD) and total numbers of binding sites (Bmax) were determined by Scatchard analysis of the saturation curves for [3H]-DHA binding.

     
  6. 6.

    There was no increase in affinity (fall in KD value) or change in the total number of binding sites associated with reserpine-induced supersensitivity. The equilibrium inhibition constant (Ki) for the displacement of [3H]-DHA binding by isoprenaline was also identical in membranes from untreated and reserpine-pretreated animals. Thus reserpine-induced supersensitivity to isoprenaline does not appear to involve a change in affinity for the β-adrenoceptor or in receptor numbers as determined by [3H]-DHA binding.

     

Key words

Cardiac β-adrenoceptors Reserpine Supersensitivity Papillary muscle [3H]-Dihydroalprenolol 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Broadley KJ, Lumley P (1977) Selective reserpine-induced supersensitivity of the positive inotropic and chronotropic responses to isoprenaline and salbutamol in guinea-pig isolated atria. Br J Pharmacol 59:51–60Google Scholar
  2. Broadley KJ, Nicholson CD (1980) The use of an irreversible β-adrenoceptor antagonist to examine reserpine and hypothermia-induced supersensitivity. J Autonomic Pharmacol 1:27–35Google Scholar
  3. Chiu TH (1978) Chronic effects of 6-hydroxydopamine and reserpine on myocardial adenylate cyclase. Eur J Pharmacol 52:385–388Google Scholar
  4. Fleming WW, Trendelenburg U (1961) The development of supersensitivity to norepinephrine after pretreatment with reserpine. J Pharmacol Exp Ther 133:41–51Google Scholar
  5. Green RD, Fleming WW (1967) Agonist-antagonist interactions in the normal and supersensitive nictitating membrane of the spinal cat. J Pharmacol Exp Ther 156:207–214Google Scholar
  6. Hudgins PM, Fleming WW (1966) A relatively non-specific supersensitivity in aortic strips resulting from pretreatment with reserpine. J Pharmacol Exp Ther 153:70–80Google Scholar
  7. Jurevics HA, Carrier O Jr (1973) The influence of reserpine on the calcium-induced responses of spontaneously beating isolated rabbit atria. J Pharmacol Exp Ther 184:189–197Google Scholar
  8. Kent RS, De Lean A, Lefkowitz RJ (1980) A quantitative analysis of beta-adrenergic receptor interactions: Resolution of high and low affinity states of the receptor by computer modeling of ligand binding data. Mol Pharmacol 17:14–23Google Scholar
  9. Koch-Weser J, Blinks JR (1963) The influence of the interval between beats on myocardial contractility. Pharmacol Rev 15:601–652Google Scholar
  10. Lefkowitz RJ, Hoffman BB (1981) New directions in adrenergic receptor reasearch. In: Lamble JW (ed) Towards understanding receptors. Current reviews in biomedicine 1. Elsevier North Holland Biomedical Press, Amsterdam, pp 61–70Google Scholar
  11. Lowry OH, Rosebrough NJ, Farr, AL, Randall RJ (1951) Protein measurements with the Folin phenol reagent. J Biol Chem 193: 265–275Google Scholar
  12. McNeill JH (1969) Researpine supersensitivity to catecholamine-induced cardiac phosphorylase activation. Can J Physiol Pharmacol 47: 515–519Google Scholar
  13. McNeill JH, Schulze S (1972) Reserpine-induced supersensitivity to histamine activated cardiac phosphorylase and cardiac contractility. Res Commun Chem Pathol Pharmacol 3:339–347Google Scholar
  14. Meisheri DK, Tenner TE Jr, McNeill JH (1979) Reserpine-induced supersensitivity to the cardiac effect of agonists. Life Sci 24:473–480Google Scholar
  15. Nohorski SR (1977) Altered responsiveness of cerebral beta adrenoceptors assessed by adenosine cyclic 3′, 5′-monophosphate formation and [3H] propranolol binding. Mol Pharmacol 13:679–689Google Scholar
  16. Scatchard G (1949) The attractions of proteins for small molecules and ions. Ann NY Acad Sci 51:660–672Google Scholar
  17. Taylor DA, Westfall DP, Fleming WW (1974) The effect of reserpine treatment on the chronotropic an dinotropic sensitivities of the perfused guinea-pig heart to norepinephrine and calcium. Eur J Pharmacol 29:102–108Google Scholar
  18. Taylor J, Green RD (1971) Analysis of reserpine sensitivity in aortic strips of rabbits. J Pharmacol Exp Ther 177:127–135Google Scholar
  19. Tenner TE Jr (1976) The influence of reserpine pretreatment on the caradiac sensitivities to calcium. Ph. D. Thesis, University of Texas Health Sciences Center at San AntonioGoogle Scholar
  20. Tenner TE Jr (1979) Reserpine induced cardiac supersensitivity. Proc West Pharmacol Soc 22:1–4Google Scholar
  21. Tenner TE Jr, Cerrier O Jr (1978) Reserpine induced supersensitivity to the chronotropic and inotropic effects of calcium on rabbit atria. J Pharmacol Exp Ther 205:183–192Google Scholar
  22. Tenner TE Jr, McNeill JH, Carrier O Jr (1978) The role of calcium in supersensitivity to the inotropic effects of norepinephrine. Eur J Pharmacol 50:359–367Google Scholar
  23. U'Prichard CD, Snyder SH (1978) 3H-catecholamine binding to α-receptors in rat brain: enhancement by researpine. Eur J Pharmacol 51: 145–155Google Scholar
  24. Waud DR, Kattegada SR, Krayer O (1958) Threshold dose and time course of norepinephrine depletion of the mammalian heart by reserpine. J Pharmacol Exp Ther 124:340–346Google Scholar
  25. Westfall DP, Fleming WW (1968) Sensitivity changes in the dog heart to norepinephrine, calcium and aminophylline resulting from pretreatment with reserpine. J Pharmacol Exp Ther 159:98–106Google Scholar

Copyright information

© Springer-Verlag 1982

Authors and Affiliations

  • Mark H. Hawthorn
    • 1
  • Kenneth J. Broadley
    • 1
  1. 1.Department of Applied Pharmacology, Welsh School of PharmacyUniversity of Wales Institute of Science and TechnologyCardiffUK

Personalised recommendations