An attempt at an analysis of the factors determining the time course of the end-plate current. I. The effects of prostigmine and of the ratio of Mg 2+  to Ca 2+ .
1. An attempt was made to analyse the factors which might determine the time course of the falling phase of the end-plate current.2. The end-plate current was measured by ;clamping' the membrane potential during neuromuscular transmission.3. The falling phase of the end-plate current was found to consist of a non-exponential, and an exponential portion, the duration of both of which varies under different experimental conditions.4. The results suggest that the rate constants determining the dissociation of the receptor-mediator complex seem greatly to influence the time course of the end-plate current.
D000818:Animals; D001001:Anura; D002118:Calcium / Q000502:physiology*; D002800:Cholinesterase Inhibitors; D004594:Electrophysiology; D066298:In Vitro Techniques; D007700:Kinetics; D008274:Magnesium / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects; D009388:Neostigmine / Q000494:pharmacology*; D009469:Neuromuscular Junction / Q000187:drug effects / Q000502:physiology*; D011893:Rana esculenta; D009435:Synaptic Transmission; D013997:Time Factors
D002800:Cholinesterase Inhibitors; D009388:Neostigmine; D008274:Magnesium; D002118:Calcium