Ultrastructural and cytochemical features of the supramedullary neurons of the pufferfish Diodon holacanthus (L.) (Osteichthyes)

摘要

Exceptionally high DNA contents were found in supramedullary neuron (SN) nuclei of the pufferfish Diodon holacanthus by quantitative microfluorimetric assay. This phenomenon has been explained by endoreplication, the functional significance of which is still unclear. In this view, the peptidergic nature and large dimensions make the teleostean clustered SN an interesting model for investigating the relationships between endoreplication, nuclear morphology and biosynthetic cellular activity.