Neuroglia in amphibian (Rana tigrina) central nervous system.

Neuroglia in the vertebrates are primarily classified as (i) Ependymal and (2) Non-ependymal gliocytes. In the present study neuroglia in the brain and spinal cord of Frog (Rana tigrina) has been studied under the light microscope using rapid Golgi, Holzer, and Luxol fast blue-neutral red staining methods. Ependymal glial cells with long processes having vascular and/or superficial terminal contacts, non-ependymal primitive glial cells (unipolar and bipolar) and phylogenetically more mature non-ependymal glial cells conforming to the classical description of astrocytes, oligodendrocytes and microgliocytes have been observed. It is interesting to note that oligodendrocytes of classical morphology have been observed in close relation to non-myelinated nerve fibres suggesting that nerve fibre-oligodendrocytes relationship may also be other than myelinogenesis.