Abstract - Using the single electrode voltage clamp method, we found that acetylcholine (ACh) induces transient inward dose-dependent current on the membrane of the identified Helix pomatia Br neuron. We analyzed the effects of fast cooling and heating as well as thermal acclimation on the ACh inward current. The experiments were conducted on active and dormant snails acclimated to either 20 or 7⁰C for at least four weeks. The Hill coefficient remained approximately 1 in all cases, which means that there is a single ACh binding site on the membrane. Fast temperature alternations induce binding affinity changes. In the work presented, we analyzed the effects of cooling on the ACh-induced inward current. The amplitude of ACh-induced inward current was markedly reduced after cooling, and the speed of decay of the ACh response was lower.