Nucleo-plasmic index variability in dorsal root ganglion neurons of the lizard (Podarcis sicula) during neuronal hypertrophy

The nucleo-plasmicindex was investigated in lizarddorsalrootganglionneurons from different spinal levels (cervical, thoracic, lumbar and caudal) in normal conditions, as well as in caudal dorsalrootganglion (DRG) neurons innervating the regenerated lizard tail (caudal hypertrophic ganglia). Results showed no statistically significant difference in the distribution of nucleo-plasmicindex values in DRGs from different spinal levels providing sensory innervation to peripheral territories of different size. On the contrary, in the caudal hypertrophic ganglia, a significant shift towards lower values of the nucleo-plasmicindex was observed. This observation suggests that this `old', and merely morphological, parameter could be regarded as a good and simple marker for the study of neuronalhypertrophy considered as a dynamic response of neurons to variations of the innervation territory.