Citation

Barthó L, Sándor Z, Bencsik T. Acta Biol. Hung. 2018; 69(2): 135-143.

Affiliation

2 Department of Pharmacognosy, Faculty of Pharmacy, University of Pécs , Rókus u. 2, H-7624 Pécs , Hungary.

Copyright

(Copyright © 2018, Akadémiai Kiadó)

DOI

10.1556/018.69.2018.2.3

PMID

29888673

Abstract

Aqueous extract of the spines of the brown bullhead catfish (Ameiurus nebulosus Lesueur, 1819) caused contraction of the guinea-pig small intestine in vitro, a widely-used preparation in pharmacology. The action is dependent on extracellular Ca²⁺, and probably takes place on the smooth muscle cells. Mouse gastrointestinal preparations were also contracted by the extract. Stings by the spines of this fish species causes a painful sensation in man. We tested the effect of an extract of spines in isolated organ experiments on innervated smooth muscle preparations. In the guinea-pig ileum, the response to the extract was abolished by the Ca²⁺-channel blocker nifedipine, but only slightly reduced by atropine (a muscarine receptor antagonist) or tetrodotoxin (TTX; a blocker axonal conduction) or antagonists for P_2X purinoceptors. Blocking of serotonin or histamine H₁ receptors, tachykinin NK₁ receptors, functional impairment of capsaicin-sensitive sensory nerve endings or inhibition of cyclo-oxygenases failed to influence the contractile effect of the extract. No inhibitory action of the extract was detected on the ileum subject to electrical motor nerve stimulation.

Language: en

Keywords

Brown bullhead catfish; smooth muscle effects; venom