[en] The cardiovascular response to 5-hydroxytryptamine (5-HT) challenge has been previously described in cattle. Abrupt bradycardia, followed by tachycardia, triphasic systemic blood pressure response, and pulmonary hypertension were the major changes elicited by 5-HT. The purpose of the present study was to determine whether the cardiovascular response to 5-HT in calves was attributable to 5-HT2 receptors. A specific 5-HT2 antagonist (metrenperone, 0.05 mg/kg) was administered intramuscular to six unsedated Friesian calves 30 min before the animals were given a 5-min intravenous 5-HT infusion. Mean systemic arterial (SAP), mean pulmonary arterial (PAP), pulmonary capillary wedge (PW) pressures were obtained by means of fluid-filled catheters, and cardiac output (CO) was measured by the thermodilution technique. Heart rate, stroke volume, systemic (SVR) and pulmonary (PVR) vascular resistances were calculated. Administration of 5-HT after metrenperone induced a short-lasting period of severe bradycardia followed by tachycardia and increased CO. The systemic blood pressure response was exclusively hypotensive and associated with a decrease in SVR. Conversely, PAP, PW, and PVR were not modified by 5-HT administration. The results establish that 5-HT induced systemic as well as pulmonary hypertension is mediated through the activation of type-2 serotonergic or alpha-adrenergic receptors, or both. In contrast, neither apnoea, bradycardia and hypotension, nor the positive chronotropic effect induced by 5-HT in cattle are mediated through such receptors.
Disciplines :
Veterinary medicine & animal health
Author, co-author :
Linden, Annick ; Université de Liège - ULiège > Département des maladies infectieuses et parasitaires > Santé et pathologies de la faune sauvage
Desmecht, Daniel ; Université de Liège - ULiège > Département de morphologie et pathologie > Pathologie spéciale et autopsies
Amory, Hélène ; Université de Liège - ULiège > Département clinique des animaux de compagnie et des équidés > Médecine interne des équidés
Lekeux, Pierre ; Université de Liège - ULiège > Département de sciences fonctionnelles > Physiologie
Language :
English
Title :
Cardiovascular Response to Intravenous Administration of 5-Hydroxytryptamine after Type-2 Receptor Blockade, by Metrenperone, in Healthy Calves
AMORY, H., LINDEN, A., DESMECHT, D., ROLLIN, F., GENICOT, B. & LEKEUX, P. (1991). Validation of the thermodilution technique for the estimation of the cardiac output in the unsedated calf. Journal of Veterinary Medicine A 38, 409-17.
APPERLEY, E., FENIUK, W., HUMPHREY, P. P. A. & LEVY, G. P. (1980). Evidence for two types of excitatory receptor for 5-hydroxytryptamine in dog isolated vasculature. British Journal of Pharmacology 68, 215-24.
BLACK, J. L., FRENCH, R. J. & MYLECHARANE, E. J. (1981). Receptor mechanisms for 5-hydroxytryptamine in rabbit arteries. British Journal of Pharmacology 74, 619-26.
BOGLE, R. G., PIRES, J. G. P. & RAMAGE, A. G. (1990). Evidence that central 5-HT1A-receptors play a role in the von Bezold-Jarisch reflex in the rat. British Journal of Pharmacology 100, 757-60.
BRADLEY, P. B., HUMPHREY, P. P. A. & WILLIAMS, R. H. (1986). Evidence for the existence of 5-hydroxytryptamine receptors which are not of the 5-HT2 type, mediating contraction of isolated rabbit basilar artery. British Journal of Pharmacology 87, 3-4.
DAROVIC, G. O. (1987). Hemodynamic Monitoring. Invasive and Noninvasive Clinical Application, ed. D. Kay, Philadelphia: WB Saunders Company.
EI-FAWAL, H. A. N., OGUNBIYI, P. O., GORDON, V. & EYRE, P. (1985). Reactivity of the bronchial artery to 5-hydroxytryptamine. Research Communications in Chemical Pathology and Pharmacology 50, 325-36.
FENIUK, W., HARE, J. & HUMPHREY, P. P. A. (1981). Analysis of the mechanism of 5-hydroxytryptamine-induced vasopressor responses in ganglion-blocked anaesthetized dogs. Journal of Pharmacy and Pharmacology 33, 155-60.
FOZARD, J. R. (1984). MDL 72222: a potent and highly selective antagonist at neuronal 5-hydroxytryptamine receptors. Naunyn-Schmiedeberg's Archives of Pharmacology 326, 36-44.
FRENKEN, M. & KAUMANN, A. J. (1984). Interaction of ketanserin and its metabolite ketanserinol with 5HT2 receptors in pulmonary and coronary arteries of calf. Naunyn-Schmiedeberg's Archives of Pharmacology 326, 334-9.
HOYER, D., CLARKE, D. E., FOZARD, J. R., et al. (1994). International union of pharmacology classification of receptors for 5-hydroxytryptamine (serotonin). Pharmacological Reviews 46, 157-98.
JANSSEN, P. A. J. (1983). 5-HT2 receptor blockade to study serotonin-induced pathology. Tips Reviews May, 198-206.
KALKMAN, H. O., BODDEKE, H. W. G. M., DOODS, H. N., TIMMERMANS, P. B. & VAN ZWIETEN, P. A. (1983). Hypotensive activity of serotonin receptor agonists in rats is related to their affinity for 5-HT1 receptors. European Journal of Pharmacology 91, 155-6.
KAUMANN, A. J. (1983). Yohimbine and rauwolscine inhibit 5-hydroxytryptamine-induced contraction of large coronary arteries of calf through blockade of 5 HT2 receptors. Naunyn-Schmiedeberg's Archives of Pharmacology 323, 149-54.
LANGER, S. Z. (1981). Presynaptic regulation of the release of catecholamines. Pharmacological Review 32, 337-62.
LINDEN, A. S., DESMECHT, D. J.-M., AMORY, H., BEDUIN, J. -M. & LEKEUX, P. M. (1996). Cardiovascular response to exogenous serotonin in healthy calves. American Journal of Veterinary Research 57, 731-8.
MELLER, S. T., LEWIS, S. J., BRODY, M. J. & GEBHART, G. F. (1992). Vagal afferent-mediated inhibition of a nociceptive reflex by i.v. serotonin in the rat. II. Role of 5-HT receptor subtypes. Brain Research 585, 71-86.
OGUNBIYI, P. O. & EYRE, P. (1984). Effects of tryptamine antagonists on the anaphylactic contractions of the bovine pulmonary smooth muscles. Journal of Veterinary Pharmacology and Therapeutics 7, 153-8.
OOMS, L. A. A. & VERHEYEN, A. K. (1982). Malignant hyperthermia: etiology, pathophysiology and prevention. In: 5-Hydroxytryptamine in Peripheral Reactions, eds F. De Clerck & P. M. Vanhoutte, pp. 129-39, New York: Raven Press.
PEROUTKA, S. J., HUANG, S. & ALLEN, G. S. (1986). Canine basilar artery contractions mediated by 5-hydroxytryptamine1a receptors. Journal of Pharmacology and Experimental Therapeutics 237, 901-6.
SAXENA, P. R. (1986). Nature of the 5-hydroxytryptamine receptors in mammalian heart. Progress in Pharmacology 6, 173-85.
SAXENA, P. R. (1989). Cardiovascular effects from stimulation of 5-hydroxytryptamine receptors. Fundamental & Clinical Pharmacology 3, 245-65.
SAXENA, P. R. & LAWANG, A. (1985). A comparison of cardiovascular and smooth muscle effects of 5-hydroxytryptamine and 5-carboxamidotryptamine, a selective agonist of 5-HT1 receptors. Archives Internationales de Pharmacodynamie 277, 235-52.
SAXENA, P. R. & VERDOUW, P. D. (1985). 5-Carboxamide tryptamine, a compound with high affinity for 5-HT1 binding sites, dilates arterioles and constricts arteriovenous anastomoses. British Journal of Pharmacology 84, 533-44.
SAXENA, P. R., MYLECHARANE, E. J. & HEILIGERS, J. (1985). Analysis of the heart rate effects of 5-hydroxytryptamine in the cat; mediation of tachycardia by 5-HT1-like receptors. Naunyn-Schmiedeberg's Archives of Pharmacology 330, 121-9.
SERTEYN, D., OOMS, L., DEGRYSE, A., COPPENS, P., , MOTTART, E. & PHILIPPART, C. (1989). Effects cardiovasculaires du R50970, une substance antisérotonine, chez le cheval anesthésié à l'halothane. Annales de Médecine Vétérinaire 133, 505-14.
VAN DE PUTTE-VAN MESSOM, G. & BURVENICH, C. (1991). The effect of ketanserin on the 5-HT-induced pressor response in the isolated bovine pulmonary artery. Archives Internationales de Physiologie, de Biochemie et de Biophysique 99, P23.
VANHOUTTE, P. M., BALL, S. G., BERDEAUX, A. et al. (1986). Mechanism of action of ketanserin in hypertension. Trends Pharmacol Sci. 7, 58-9.
VAN NUETEN, J. M., LEYSEN, J. E., VANHOUTTE, P. M. & JANSSENS, P., A. J. (1982a). Serotonergic responses in vascular and non-vascular tissues. Archives Internationales de Pharmacodynamie et de Thérapie 256, 331-4.
VAN NUETEN, J. M., JANSSEN, P. A. J., DE RIDDER, W. & VANHOUTTE, P. M. (1982b). Interaction between 5-hydroxytryptamine and other vasoconstrictor substances in the isolated femoral artery of the rabbit: effect of ketanserin (R41468). European Journal of Pharmacology 77, 281-7.
