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PubMed · 497526

Coronary anaphylaxis in vitro.

N Chand·P Eyre
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Abstract

1 The reactivity of isolated coronary arteries and cardiac veins of the calf to selected chemical mediators of anaphylaxis and to sensitizing antigen (horse plasma) was studied. 2 Both the coronary arteries and cardiac veins contracted to bradykinin, 5-hydroxytryptamine (5-HT), prostaglandin E2 (PGE2), PGF2 alpha, histamine and carbachol. 3 Isoprenaline and PGE1 relaxed vessels which had been partially contracted by PGF2 alpha, PGE2, histamine, 5-HT, bradykinin, carbachol or antigen. 4 Horse plasma (antigen) contracted coronary vessels obtained from sensitized calves, but not from control calves. Subsequent antigen 'challenge' produced 'densensitization' (tachphylaxis). After 1 or 2 h of rest, the anaphylactic response partially recovered although there was no change in tissue reactivity to the exogenous agonists. 5 Specific doses of atropine, mepyramine (H1-blocker) and methysergide (5-HT antagonist) did not modify the anaphylactic reaction in coronary arteries, suggesting a negligible role for these biogenic amines. 6 Compound PRD-92-EA (a new anti-allergic agent) exhibited non-specific receptor blocking activity towards histamine, 5-HT and carbachol and inhibited the coronary anaphylactic reaction.

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AnaphylaxisAnimalsAtropineCarbacholCattleCoronary VesselsHistamineIn Vitro TechniquesMaleMethysergideMuscle ContractionMuscle, SmoothPyrilamineSerotoninJournal Article

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BibTeXRIS

N Chand, P Eyre. 1979. Coronary anaphylaxis in vitro.. https://doi.org/10.1111/j.1476-5381.1979.tb08666.x

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