Topographical differences of carboxylic esterases in the rhombencephalon and mesencephalon of the turtle (Lissemys punctata granosa).

The present contribution deals with histochemical mapping of acetylcholinesterase, butyrylcholinesterase and non-specific esterase in the rhombencephalon and mesencephalon of the turtle (L. punctata). The study reveals that all the neurons of this species are strongly positive for AChE, irrespective of their sensory or motor nature. The enzyme is localized in cell bodies and dendritic processes, while the axons are completely negative. Thus its presence in the fibrous components is not seen except in the superficial layers of optic tectum. Non-specific esterase activity is quite prominent in all the neurons, while the neuropil is weakly positive in most of the nuclei with a few exceptions. The blood vessels are strongly positive throughout the area. In sharp contrast to these enzymes. BChE is completely missing in all the constituents.