Naunyn-Schmiedeberg's Archives of Pharmacology

, Volume 328, Issue 1, pp 30–32 | Cite as

Effect of pithing on the postjunctional sympatho-inhibitory action of captopril in cats

  • Adriaan de Jonge
  • David Davidesko
  • Marie-Jeanne Mathy
  • Martin J. M. C. Thoolen
  • Bob Wilffert
  • Peter van Brummelen
  • Pieter B. M. W. M. Timmermans
  • Pieter A. van Zwieten
Article

Summary

Pithing of anaesthetized normotensive cats significantly lowered the arterial blood pressure and augmented plasma renin activity (PRA). Captopril dose-dependently diminished mean arterial blood pressure in both pithed and intact anaesthetized normotensive cats. The hypotensive effectiveness of captopril was most pronounced in pithed cats. Captopril inhibited the hypertensive response to intravenously administered noradrenaline in pithed cats, but did not attenuate the hypertensive response to noradrenaline in intact cats. The results do not exclude that the hypotensive activity of captopril in intact cats may be causally independent of the attenuating effect of converting enzyme inhibition on the postjunctional α-adrenoceptor mediated vasoconstriction as observed in pithed animals.

Key words

Captopril Pithed and intact anaesthetized normotensive cats Inhibition of α-adrenoceptor mediated vasoconstriction 

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References

  1. Antonaccio MJ, Kerwin MS (1981) Pre- and postjunctional inhibition of vascular sympathetic function by captopril in SHR; implication of vascular angiotensin II in hypertension and antihypertensive actions of captopril. Hypertension 6 (Suppl I):I54-I62Google Scholar
  2. Clough DP, Hatton R, Keddie JR, Collis MG (1982) Hypotensive action of captopril in spontaneously hypertensive and normotensive rats: Interference with neurogenic vasoconstriction. Hypertension 4:764–772Google Scholar
  3. Day MD, Moore AF (1976) Interaction of angiotensin II with noradrenaline and other spasmogens on rabbit isolated aortic strips. Arch Int Pharmacodyn 219:29–44Google Scholar
  4. Hatton R, Clough DP (1982) Captopril interferes with neurogenic constriction in the pithed rat by angiotensin dependent mechanisms. J Cardiovasc Pharmacol 4:116–123Google Scholar
  5. Ichikawa S, Johnson JA, Fowler WL, Payne CG, Kurz K, Keitzer WF (1978) Pressor responses to norepinephrine in rabbits with 3-day and 30-day renal artery stenosis; the role of angiotensin II. Circ Res 43:437–446Google Scholar
  6. De Jonge A, Wilffert B, Kalkman HO, Van Meel JCA, Thoolen MJMC, Timmermans PBMWM, van Zwieten PA (1981) Captopril impairs the vascular smooth muscle contraction mediated by postsynaptic α2-andrenoceptors in the pitched rat. Eur J Pharmacol 74:385–386Google Scholar
  7. De Jonge A, Knape JThA, Wilffert B, Kalkman HO, Van Meel JCA, Thoolen MJMC, Timmermans PBMWM, Van Zwieten PA (1982) Effect of converting enzyme inhibition and angiotensin receptor blockade on the vasoconstriction mediated by α1 and α2-andrenoceptors in pithed normotensive rats. Naunyn-Schmiedeberg's Arch Pharmacol 321:309–313Google Scholar
  8. De Jonge A, Knape JThA, Van Meel JCA, Kalkman HO, Wilffert B, Thoolen MJMC, Van Brummelen P, Timmermans PBMWM, Van Zwieten PA (1983) Effect of captopril on sympathetic neurotransmission in pithed normotensive rats. Eur J Pharmacol 88:231–240Google Scholar
  9. Lai EM, Tanikella T, Herzlinger H, Thibault L, Cervoni P (1981) Effects of continuous angiotensin I converting enzyme blockade on blood pressure, sympathetic activity and reninangiotensin system in stroke-prone spontaneously hypertensive rats. Life Sci 28:1309–1316Google Scholar
  10. Nicholas TE (1970) Potentiation of the effects of noradrenaline and of sympathetic stimulation of the perfused caudal artery by angiotensin. J Pharm Pharmacol 22:37–41Google Scholar
  11. Redleaf PD, Tobian L (1958) The question of vascular hyperresponsiveness in hypertension. Circ Res 6:185–193Google Scholar
  12. Schümann HJ, Lues I (1983) Postjunctional α-adrenoceptors in the isolated saphenous vein of the rabbit; characterization and influence of angiotensin. Naunyn-Schmiedeberg's Arch Pharmacol 323:328–334Google Scholar
  13. Wallenstein S, Zucker CL, Fleiss JL (1980) Some statistical methods useful in circulation research. Circ Res 47:1–9Google Scholar

Copyright information

© Springer-Verlag 1984

Authors and Affiliations

  • Adriaan de Jonge
    • 1
  • David Davidesko
    • 1
  • Marie-Jeanne Mathy
    • 1
  • Martin J. M. C. Thoolen
    • 1
  • Bob Wilffert
    • 1
  • Peter van Brummelen
    • 2
  • Pieter B. M. W. M. Timmermans
    • 2
  • Pieter A. van Zwieten
    • 2
  1. 1.Department of Pharmacy, Division of PharmacotherapyUniversity of AmsterdamAmsterdamThe Netherlands
  2. 2.Department of Nephrology, Academical HospitalUniversity of LeidenLeidenThe Netherlands

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