Analysis of responses of Leidynema appendiculata to acetylcholine using electrophysiological techniques

The electrophysiological responses of adult females of the insect-parasitic nematode Leidynema appendiculata, to 100 mM. 10 mM, and 1 mM acetylcholine were concentration dependent, with stimulation by 100 mM acetylcholine giv ing the largest increase in spike activity. By contrast. the delay in respo nse was not concentration dependent. No increase in activity was obtained o n stimulation with either 0.1 mM acetylcholine or phosphate-buffered saline . The lack of response to 0.1 mM acetylcholine was confirmed by sequential exposure of L. appendiculata to 0.1 mM acetylcholine and subsequently to 10 mM acetylcholine.