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British Journal of Pharmacology logoLink to British Journal of Pharmacology
. 1993 Sep;110(1):289–296. doi: 10.1111/j.1476-5381.1993.tb13807.x

A facilitatory effect of anti-angiotensin drugs on vagal bradycardia in the pithed rat and guinea-pig.

M Rechtman 1, H Majewski 1
PMCID: PMC2175998  PMID: 8220890

Abstract

1. In pithed rats, preganglionic vagal nerve stimulation (at 5 Hz) elicited a bradycardia. This bradycardia was potentiated by the angiotensin converting enzyme inhibitor, captopril (1 mg kg-1, i.v.) by about 40%. Subsequent angiotensin II infusion (0.03 micrograms kg-1 min-1) reversed this effect. A similar facilitatory effect was also seen with the angiotensin receptor antagonist, losartan (10 mg kg-1, i.v.). These results suggest a tonic inhibitory effect of endogenous angiotensin II on vagal transmission. 2. The effect of captopril in potentiating vagal bradycardia appears to be at the level of vagal neurones, since the bradycardia elicited by the muscarinic agonist, methacholine was unaffected. 3. After the pithed rats were nephrectomized, captopril had no effect on vagally-induced bradycardia, suggesting that the formation of the endogenous angiotensin II responsible for the effect was dependent on renin release from the kidney. 4. When the sympathetic nerves of the pithed rat were electrically stimulated there was a tachycardia, and this was unaffected by captopril. However, when the sympathetic and vagus nerves were activated concurrently, the resulting tachycardia was inhibited by captopril. 5. In pithed guinea-pigs, captopril also potentiated the bradycardia caused by vagal nerve stimulation. This appears to be a tissue-selective effect since the bronchoconstriction due to the vagal stimulation was not affected by captopril. 6. These results suggest that endogenous angiotensin II can have a tonic inhibitory effect on cardiac vagal transmission. Disruption of this mechanism by anti-angiotensin drugs may attenuate the reflex tachycardia associated with the fall in blood pressure in anti-hypertensive therapy.

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Selected References

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  1. Andrews P. L., Dutia M. B., Harris P. J. Angiotensin II does not inhibit vagally-induced bradycardia or gastric contractions in the anaesthetized ferret. Br J Pharmacol. 1984 Aug;82(4):833–837. doi: 10.1111/j.1476-5381.1984.tb16480.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Boulet L. P., Milot J., Lampron N., Lacourcière Y. Pulmonary function and airway responsiveness during long-term therapy with captopril. JAMA. 1989 Jan 20;261(3):413–416. [PubMed] [Google Scholar]
  3. Boura A. L., Hui S. C., Ishac E. J., Rechtman M. P., Walters W. A. Attenuation by captopril of pressor responses to peripheral sympathetic nerve stimulation in rats is abolished after bilateral nephrectomy and during mineralocorticoid hypertension. Clin Exp Pharmacol Physiol. 1983 May-Jun;10(3):283–287. doi: 10.1111/j.1440-1681.1983.tb00198.x. [DOI] [PubMed] [Google Scholar]
  4. Boura A. L., Rechtman M. P., Walters W. A. Attenuation by captopril of pressor responses to sympathetic stimuli: effects of procedures reducing activity of the renin-angiotensin system. J Auton Pharmacol. 1983 Sep;3(3):203–211. doi: 10.1111/j.1474-8673.1983.tb00536.x. [DOI] [PubMed] [Google Scholar]
  5. Campbell B. C., Sturani A., Reid J. L. Evidence of parasympathetic activity of the angiotensin converting enzyme inhibitor, captopril, in normotensive man. Clin Sci (Lond) 1985 Jan;68(1):49–56. doi: 10.1042/cs0680049. [DOI] [PubMed] [Google Scholar]
  6. Chiu A. T., Herblin W. F., McCall D. E., Ardecky R. J., Carini D. J., Duncia J. V., Pease L. J., Wong P. C., Wexler R. R., Johnson A. L. Identification of angiotensin II receptor subtypes. Biochem Biophys Res Commun. 1989 Nov 30;165(1):196–203. doi: 10.1016/0006-291x(89)91054-1. [DOI] [PubMed] [Google Scholar]
  7. Edwards C. R., Padfield P. L. Angiotensin-converting enzyme inhibitors: past, present, and bright future. Lancet. 1985 Jan 5;1(8419):30–34. doi: 10.1016/s0140-6736(85)90975-4. [DOI] [PubMed] [Google Scholar]
  8. Erdös E. G., Johnson A. R., Boyden N. T. Hydrolysis of enkephalin by cultured human endothelial cells and by purified peptidyl dipeptidase. Biochem Pharmacol. 1978 Mar 1;27(5):843–848. doi: 10.1016/0006-2952(78)90542-7. [DOI] [PubMed] [Google Scholar]
  9. Gillespie J. S., Maclaren A., Pollock D. A method of stimulating different segments of the autonomic outflow from the spinal column to various organs in the pithed cat and rat. Br J Pharmacol. 1970 Oct;40(2):257–267. doi: 10.1111/j.1476-5381.1970.tb09919.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Giudicelli J. F., Berdeaux A., Edouard A., Richer C., Jacolot D. The effect of enalapril on baroreceptor mediated reflex function in normotensive subjects. Br J Clin Pharmacol. 1985 Sep;20(3):211–218. doi: 10.1111/j.1365-2125.1985.tb05063.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Hatton R., Clough D. P. Captopril interferes with neurogenic vasoconstriction in the pithed rat by angiotensin-dependent mechanisms. J Cardiovasc Pharmacol. 1982 Jan-Feb;4(1):116–123. doi: 10.1097/00005344-198201000-00019. [DOI] [PubMed] [Google Scholar]
  12. Johnston C. I., Arnolda L., Hiwatari M. Angiotensin-converting enzyme inhibitors in the treatment of hypertension. Drugs. 1984 Mar;27(3):271–277. doi: 10.2165/00003495-198427030-00006. [DOI] [PubMed] [Google Scholar]
  13. Kondowe G. B., Deering A. H., Riddell J. G., Johnston G. D., Harron D. W. The effect of acute and chronic captopril therapy on baroreflex function in man. Br J Clin Pharmacol. 1988 Mar;25(3):315–321. doi: 10.1111/j.1365-2125.1988.tb03309.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Lee W. B., Ismay M. J., Lumbers E. R. Mechanisms by which angiotensin II affects the heart rate of the conscious sheep. Circ Res. 1980 Aug;47(2):286–292. doi: 10.1161/01.res.47.2.286. [DOI] [PubMed] [Google Scholar]
  15. Levy M. N., Martin P. J., Stuesse S. L. Neural regulation of the heart beat. Annu Rev Physiol. 1981;43:443–453. doi: 10.1146/annurev.ph.43.030181.002303. [DOI] [PubMed] [Google Scholar]
  16. Lindpaintner K., Ganten D. Tissue renin-angiotensin systems and their modulation: the heart as a paradigm for new aspects of converting enzyme inhibition. Cardiology. 1991;79 (Suppl 1):32–44. doi: 10.1159/000174905. [DOI] [PubMed] [Google Scholar]
  17. Lumbers E. R., McCloskey D. I., Potter E. K. Inhibition by angiotensin II of baroreceptor-evoked activity in cardiac vagal efferent nerves in the dog. J Physiol. 1979 Sep;294:69–80. doi: 10.1113/jphysiol.1979.sp012915. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Löffelholz K., Muscholl E. Inhibition by parasympathetic nerve stimulation of the release of the adrenergic transmitter. Naunyn Schmiedebergs Arch Pharmakol. 1970;267(2):181–184. doi: 10.1007/BF00999400. [DOI] [PubMed] [Google Scholar]
  19. Majewski H. Angiotensin II and noradrenergic transmission in the pithed rat. J Cardiovasc Pharmacol. 1989 Oct;14(4):622–630. doi: 10.1097/00005344-198910000-00014. [DOI] [PubMed] [Google Scholar]
  20. Majewski H., Hedler L., Schurr C., Starke K. Modulation of noradrenaline release in the pithed rabbit: a role for angiotensin II. J Cardiovasc Pharmacol. 1984 Sep-Oct;6(5):888–896. doi: 10.1097/00005344-198409000-00023. [DOI] [PubMed] [Google Scholar]
  21. Mancia G., Giannattasio C., Grassi G., Morganti A., Zanchetti A. Reflex control of circulation and angiotensin converting enzyme inhibition in man. J Hypertens Suppl. 1988 Dec;6(3):S45–S49. [PubMed] [Google Scholar]
  22. Mian M. A., Majewski H., Rand M. J. Facilitation of noradrenaline release by isoprenaline in rat isolated atria does not involve angiotensin II formation. Clin Exp Pharmacol Physiol. 1989 Dec;16(12):905–911. doi: 10.1111/j.1440-1681.1989.tb02401.x. [DOI] [PubMed] [Google Scholar]
  23. Muscholl E. Peripheral muscarinic control of norepinephrine release in the cardiovascular system. Am J Physiol. 1980 Dec;239(6):H713–H720. doi: 10.1152/ajpheart.1980.239.6.H713. [DOI] [PubMed] [Google Scholar]
  24. Potter E. K. Angiotensin inhibits action of vagus nerve at the heart. Br J Pharmacol. 1982 Jan;75(1):9–11. doi: 10.1111/j.1476-5381.1982.tb08752.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Potter E. K. Peripheral inhibition of the parasympathetic nervous system by angiotensin. Clin Exp Pharmacol Physiol Suppl. 1982;7:51–55. [PubMed] [Google Scholar]
  26. Rechtman M. P., Boura A. L., King R. G., Olley J. E., Schiller P. W. Effects of morphine, H-Tyr-D-Arg-Phe-Lys-NH2 (DALDA) and B-HT920 on non-cholinergic nerve-mediated bronchoconstriction in pithed guinea-pigs. Br J Pharmacol. 1990 Oct;101(2):269–272. doi: 10.1111/j.1476-5381.1990.tb12699.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Rose'Meyer C. M., Rechtman M. P., Boura A. L., King R. G. Presynaptic alpha 2-adrenoreceptors affecting terminal synaptic transmission by the nervi cardiaci accelerantes in the rat. J Auton Pharmacol. 1989 Apr;9(2):119–127. doi: 10.1111/j.1474-8673.1989.tb00203.x. [DOI] [PubMed] [Google Scholar]
  28. Scroop G. C., Lowe R. D. Efferent pathways of the cardiovascular response to vertebral artery infusions of angiotensin in the dog. Clin Sci. 1969 Dec;37(3):605–619. [PubMed] [Google Scholar]
  29. Sebastian J. L., McKinney W. P., Kaufman J., Young M. J. Angiotensin-converting enzyme inhibitors and cough. Prevalence in an outpatient medical clinic population. Chest. 1991 Jan;99(1):36–39. doi: 10.1378/chest.99.1.36. [DOI] [PubMed] [Google Scholar]
  30. Soffer R. L. Angiotensin-converting enzyme and the regulation of vasoactive peptides. Annu Rev Biochem. 1976;45:73–94. doi: 10.1146/annurev.bi.45.070176.000445. [DOI] [PubMed] [Google Scholar]
  31. Starke K. Regulation of noradrenaline release by presynaptic receptor systems. Rev Physiol Biochem Pharmacol. 1977;77:1–124. doi: 10.1007/BFb0050157. [DOI] [PubMed] [Google Scholar]
  32. Sturani A., Chiarini C., Degliesposti E., Santoro A., Zuccalà A., Zucchelli P. Heart rate control in hypertensive patients treated by captopril. Br J Clin Pharmacol. 1982 Dec;14(6):849–855. doi: 10.1111/j.1365-2125.1982.tb02048.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Subissi A., Guelfi M., Criscuoli M. Angiotensin converting enzyme inhibitors potentiate the bronchoconstriction induced by substance P in the guinea-pig. Br J Pharmacol. 1990 Jul;100(3):502–506. doi: 10.1111/j.1476-5381.1990.tb15837.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Weber M. A. Safety issues during antihypertensive treatment with angiotensin converting enzyme inhibitors. Am J Med. 1988 Apr 15;84(4A):16–23. doi: 10.1016/0002-9343(88)90465-2. [DOI] [PubMed] [Google Scholar]
  35. Wong P. C., Price W. A., Jr, Chiu A. T., Duncia J. V., Carini D. J., Wexler R. R., Johnson A. L., Timmermans P. B. In vivo pharmacology of DuP 753. Am J Hypertens. 1991 Apr;4(4 Pt 2):288S–298S. doi: 10.1093/ajh/4.4.288s. [DOI] [PubMed] [Google Scholar]
  36. Wong P. C., Price W. A., Jr, Chiu A. T., Duncia J. V., Carini D. J., Wexler R. R., Johnson A. L., Timmermans P. B. Nonpeptide angiotensin II receptor antagonists. XI. Pharmacology of EXP3174: an active metabolite of DuP 753, an orally active antihypertensive agent. J Pharmacol Exp Ther. 1990 Oct;255(1):211–217. [PubMed] [Google Scholar]
  37. Zimmerman B. G. Actions of angiotensin on adrenergic nerve endings. Fed Proc. 1978 Feb;37(2):199–202. [PubMed] [Google Scholar]
  38. de Jonge A., Knape J. T., van Meel J. C., Kalkman H. O., Wilffert B., Thoolen M. J., Timmermanns P. B., van Zwieten P. A. Effect of converting enzyme inhibition and angiotensin receptor blockade on the vasoconstriction mediated by alpha 1-and alpha 2-adrenoceptor stimulation in pithed normotensive rats. Naunyn Schmiedebergs Arch Pharmacol. 1982 Dec;321(4):309–313. doi: 10.1007/BF00498519. [DOI] [PubMed] [Google Scholar]

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