COMPARATIVE EFFECTS OF THE ANTICHOLINESTERASE DRUG GALANTHAMINE ON THE MECHANICAL-ACTIVITY OF ISOLATED RAT JEJUNUM AND ILEUM

1. The effects of cumulatively applied galanthamine hydrobromide (0.1- 300 muM) on the mechanical activity of isolated proximal jejunum and d istal ileum were studied. 2. Galanthamine was found to increase the sp ontaneous mechanical activity and exert by itself an enhancement of th e smooth muscle tone in the two segments, both effects being more pron ounced in ileum than in jejunum. 3. The galanthamine-induced augmentat ion of the spontaneous mechanical activity was tetrodotoxin (TTX)-sens itive, whereas the contractile effect of the drug on the tone was TTX- insensitive in both segments. 4. The present results showed not only q uantitative differences in the tonic effects of galanthamine in both i ntestinal segments but they suggest some qualitative differences in ch olinergic neuronal control along the gastro-intestinal tract.