ISSN:
1420-908X
Keywords:
Key words: Ephedrine – Stomach – Passive cutaneous anaphylaxis – Adrenergic nerve – Adrenoceptor
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract. Objective and Design: We previously demonstrated that oral l-ephedrine exerts an extremely rapid (within 20 s) inhibition of 48-h passive cutaneous anaphylaxis reaction (PCA) in rats by a possibly unidentified mode of action. In the present experiments, we elucidated the mechanism of the PCA inhibition by l-ephedrine using adrenoceptor agonists and antagonists.¶Materials: Rat antiserum was prepared with dinitrophenylated Ascaris suum extract + Bordetella pertussis.¶Treatment: Passively skin-sensitised Wistar rats were mainly used. l-Ephedrine, and adrenoceptor agonists and antagonists were orally administered immediately before PCA provocation. Catecholamine depleting (6-hydroxydopamine, 6-OH-DA), amine depleting (reserpine) or ganglion blocking (hexamethonium) agent was intraperitoneally or intravenously administered before the provocation.¶Methods: The effects of the drugs on PCA were assessed by inhibition of the dye leakage.¶Results: β-(propranolol) and β 2-(butoxamine) blocking agents reduced the inhibition of PCA by l-ephedrine, while the inhibition was not altered by either an α-blocking agent (phentolamine) or a β 1-(atenolol) selective antagonist. On the other hand, β-(isoproterenol) and β 2-selective (salbutamol) agonists showed extremely rapid inhibition of PCA. However, the β 1-selective agonist (dobutamine) had no effect on the reaction. The pretreatment with hexamethonium, reserpine or 6-OH-DA substantially attenuated the inhibitory effect of l-ephedrine on PCA.¶Conclusions: The results strongly suggest that β 2-adrenoceptors locate in the stomach and that their receptor excitement finally may lead to the inhibition of PCA via the stimulation of the central and peripheral nervous systems.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s000110050651
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