The role of intrinsic, non-adrenergic, non-cholinergic inhibitory nerves in the regulation of distensibility of the guinea-pig colon.
1. The lengthening responses of segments of distal colon of guinea-pigs to applied weights were measured. 2. Distensibility was reduced by tetrodotoxin and quinidine; increased by atropine and hyoscine, and unaffected by guanethidine and phentolamine. 3. Tension changes produced by controlled stretches were increased by tetrodotoxin. 4. These results suggest that there is a net, inhibitory, non-adrenergic, non-cholinergic influence acting on the muscle during stretch against a background of cholinergic excitatory tone. This inhibitory activity may be activated reflexly by stretch.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D003106:Colon / Q000187:drug effects / Q000294:innervation* / Q000502:physiology; D005769:Gastrointestinal Motility; D006145:Guanethidine / Q000494:pharmacology; D006168:Guinea Pigs; D066298:In Vitro Techniques; D009433:Neural Inhibition; D010646:Phentolamine / Q000494:pharmacology; D011802:Quinidine / Q000494:pharmacology; D012601:Scopolamine / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology
D013779:Tetrodotoxin; D001285:Atropine; D012601:Scopolamine; D011802:Quinidine; D010646:Phentolamine; D006145:Guanethidine