The Morphological Evidence on the Various Subpopulations of Neurons in L_6 DRG of Adult Cat by Criterion of Size

To explore the relation between the size of neuron and various populations,the L 6 dorsal root ganglion (DRG) was made into 20 μm frozen section in thickness and the average diameters of neuron in L 6 DRG of adult cat were measured. Results: It has been possible to show tentatively that there are three populations of cytons by diameter in DRG of adult cat. The average diameter and percentage of large,intermediate and small cytons were respectively: 42 μm,42～57 μm,57 μm; 29%,22%,49%. The results provided the criterion of size for discriminating from various subpopulations in DRG of adult cat.