[Relationship between the spike responses of crayfish mechanoreceptor neurons and the initial functional state and degree of aggregation of their Nissl substance].

The discharges of a single neuron in the crayfish isolated stretch receptor to square standard adequate stimuli were studied. The following parameters were analyzed: response duration, number of impulses per burst, inhibitory pause duration, amplitude and shape of the frequencygram. Preliminary desaggregation of Nissl substance correlated with increase in discharges. When initial frequency of the discharge was low or when the stretch receptor was in resting state, especially in winter time, and the Nissl substance showed high degree of aggregation, discharges to the same stimuli were weaker, and their range diminished. It is suggested that intensified discharges are determined by intracellular redistribution and uptake of calcium which take place during desaggregation of the Nissl substance.