Kazan National Research Technical University named after A.N. Tupolev 1 article published in JoVE Neuroscience Registration of Calcium Transients in Mouse Neuromuscular Junction with High Temporal Resolution using Confocal Microscopy Nikita V. Zhilyakov1, Arsenii Y. Arkhipov1, Eduard F. Khaziev1,2, Marat A. Mukhamedyarov3, Dmitry V. Samigullin1,2 1Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, 2Department of Radiophotonics and Microwave Technologies, Kazan National Research Technical University named after A.N. Tupolev, 3Department of Normal Physiology, Kazan State Medical University The protocol describes the method of loading a fluorescent calcium dye through the cut nerve into mouse motor nerve terminals. In addition, a unique method for recording fast calcium transients in the peripheral nerve endings using confocal microscopy is presented.