Structural and Cytochemical Organization of Synapses

Abstract

The results of structural, cytochemical and pharmacological studies of the synapses of sensory organs were usually examined from the standpoint of their similarity with what we know about the synapses of the central nervous system (de Robertis, 1958, 1964; de Robertis et al., 1961; Whittaker and Gray, 1962; Gray, 1963, 1967, 1969; Robertson, 1964; Eccles, 1964; Whittaker, 1965, 1967; Gray and Guylliery, 1966; Roberts et al., 1967). Among peripheral synapses, nerve-muscle connections in vertebrates have been studied most extensively (Couteaux, 1958; Birks, Huxley, and Katz, 1960; Robertson et al., 1960b). At the same time, it is quite obvious that the differences in their structural and cytochemical organization must also be clarified. No less important is the clarification of the question whether synapses of receptor cells are mediator-ones (i.e. they transmit a stimulus by liberating a chemical substance) or whether they are ephaptic (i.e. they operate by means of electrical transmission). Finally, what are our present concepts of synaptic transmission in general? This is the range of problems we propose to examine in this chapter.