Ultrastructure of neuronal cell bodies in the dorsal cortex of Lacerta galloti

According to ultrastructure, size and location within the dorsal cortex of Lacerta galloti, six basic types of neuronal somata are described in this study. In the outer plexiform layer only few neuronal somata with nuclear invaginations can be detected (type A). In the granular stratum, large neuronal somata (type B) receiving axo-somatic synapses and covered by ependymoglial ramifications represent 60% of all somata of the dorsal cortex. In the inner plexiform layer, a heterogeneous population of somata according to their ultrastructure can be detected. These are: big neuronal somata (type C), neuronal somata with nuclear invaginations (type D), neuronal somata having many dense core vesicles (type E), and neuronal somata associated to the ependymal layer (type F). There, also groups or "nests" of neuronal somata closely attached and partially covered by ependymoglial branches can be seen. Because of the simple cytoarchitectonic scheme of this dorsal cortex, location of somata, frequency, and biometrical characteristics they have been used to make comparisons with neuronal types defined by Golgi impregnations in the dorsal cortex of Lacerta galloti (Regidor 1977). Nevertheless, grouped neuronal somata of the inner plexiform layer are difficult to correlate; also the presence of immature neuronal somata in this area leads to the possibility of existing a subependymary zone remaining some embryonary characteristics.