Facilitation in sea anemones; the action of drugs.

摘要: 1. The action of a number drugs which affect the neuromuscular systems vertebrates has been examined on sea anemone, Calliactis parasitica . In contrast to their in vertebrates, no directly cause contraction muscles anemone. 2. Some group act at cholinergic junctions including acetylcholine itself, were ineffective Atropine and nicotine, same group, had depressant effects. 3. adrenergic adrenaline On other hand, tyramine, tryptamine 933 F enhanced sensitized response nervous excitation. Thus responses single stimuli occurred, whereas normally only follow second subsequent stimuli. Cocaine ergotoxme depressed manner analogous effects vertebrates. 4. No significant observed with substances, strychnine, veratrine, histamine, betaine tetramethylammonium hydroxide. 5. limitation drug enhancement sensitization supports view that transmission cannot be simple chemical process as general results support hypothesis there is separate must precede excitation muscle these animals. have sensitizing do not possess all properties would expected natural ‘sensitizer’ or ‘facilitator’ carrying out this nerve ending.