[Distribution of nerve fiber nodes with different cytochemical properties in bushy interoceptors].

Distribution of generation zones of the action potential (AP) in the bushy interoceptors of the frog urinary bladder has been studied by means of D. C. Quick and S. G. Waxman cytochemical technique (1977). A positive reaction is obtained from the nodes of the neural fibers and a part of semi-nodi. The dependence of active nodi distribution on the length of the myelin branches is revealed. Three variants in distribution of precipitate are found in the divided fibers. If the distance between the semi-nodi is 60-350 mcm, the precipitate deposits more proximal to the node division. When the distance between the semi-nodi is 1,300-1,650 mcm, the active nodi are in both branches of the divided fiber. When the distance between the semi-nodi is 460-940 mcm, the active nodi are either in one branch only, or no branches give any positive reaction, and the precipitate deposits in the node of branching. Since the precipitate deposition characterizes, according to D. C. Quick and S. G. Waxman (1977) data, the AP generation places, it is possible to suppose that several impulse generators are present in one receptor, when the distance between its semi-nodi is not less than 1,300 mcm. A specific precipitate is supposed to deposit in the plates. It speaks in favour of a great density of transmembranous currents that determine transformation of a mechanical stimulus into a receptory potential.