Immediate X-radiation induced contractions of the isolated guinea pig terminal ileum: the localization of the effect by drugs.

摘要: Tone and motility of the isolated guinea pig ileum were increased by irradiation with a dose 10 krd. The maximal effect corresponds to that induced 0.001 µg/ml acetylcholine or 0.3 nicotine. pharmacological analysis this performed nicotine several blocking agents including hexamethonium, atropine, tetrodotoxin, diphenhydramine, verapamil suggests radiation acts on postganglionic parasympathetic neuron neuromuscular synapse. mechanism is likely consist both an release from sensibilization cholinergic receptor site at smooth muscle cell. latter thought result contractile action in irradiated ileal muscle.