title: Acetylcholine and an unidentified, muscle-contracting factor in the venom of the bumblebee, Bombus terrestris L.
abstract: Extracts of venom reservoirs as well as dilutions of venom droplets collected from the tip of the sting of Bombus terrestris were tested for biological activity on the isolated guinea-pig ileum, the frog rectus abdominis, and the rat phrenic nerve-hemidiaphragm preparation. The venom contains a cholinergic factor, apparently identical to acetylcholine, at a concentration of about 30 micrograms per venom reservoir. This was confirmed using radioimmunoassay of acetylcholine. The venom also contains a component causing a slow contraction of guinea-pig ileum and rat diaphragm. This component is heat stable, non dialysable, and is slowly destroyed in the venom preparation at about 0 degrees C.
mesh_terms: D000109:Acetylcholine / Q000032:analysis* / Q000494:pharmacology; D000818:Animals; D001514:Bee Venoms / Q000032:analysis* / Q000494:pharmacology; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects; D009388:Neostigmine / Q000494:pharmacology; D011898:Ranidae; D051381:Rats
chemical_list: D001514:Bee Venoms; D009388:Neostigmine; D000109:Acetylcholine