[Interferometric study of a single living neuron in relation to its electrical activity]

Interferometric microscopic study of living neurons of the isolated brain of Limnaea stagnalis has revealed some fluctuation of dry weight of the cytoplasm and the nucleolus in the absence of electrical activity of the neuron. The character of these changes was different for different neurons. During the neuron-induced generation of action potentials in response to the intracellular electrical stimulation, the changes in dry weight became similar for all neurons: the dry weight of the cytoplasm increased and the dry weight of the nucleolus decreased. This effect grew with the time of stimulation.