TY  - JOUR
PY  - 2018//
TI  - Effects of the venom of the brown bullhead catfish (Ameiurus nebulosus) on isolated smooth muscles
JO  - Acta biologica Hungarica
A1  - Barthó, Loránd
A1  - Sándor, Zsolt
A1  - Bencsik, Timea
SP  - 135
EP  - 143
VL  - 69
IS  - 2
N2  - 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 Ca<sup>2+</sup>, 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 Ca<sup>2+</sup>-channel blocker nifedipine, but only slightly reduced by atropine (a muscarine receptor antagonist) or tetrodotoxin (TTX; a blocker axonal conduction) or antagonists for P<sub>2X</sub> purinoceptors. Blocking of serotonin or histamine H<sub>1</sub> receptors, tachykinin NK<sub>1</sub> 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.<p />  <p>Language: en</p>
LA  - en
SN  - 0236-5383
UR  - http://dx.doi.org/10.1556/018.69.2018.2.3
ID  - ref1
ER  -