Deprenyl increases synaptophysin and choline acetyltransferase in rat after sciatic nerve axotomy

Neuroprotective effect of deprenyl on motoneurons of spinal cord after axotomy of peripheral nerves such as sciatic has been well established. Deprenyl is an inhibitor of monoamine oxidase type-B (MAO-B). The main function of this agent is the release of neurotransmitters from pre-synaptic terminals. Acetylcholine is a neurotransmitter that is synthesized by choline acetyltransferase (ChAT) and is widely used as a marker to assess the function of neurons. Synaptophysin is one of the synaptic vesicle neuronal terminal residual proteins which is also used as a marker for some neurotransmitters.The aim of this research was to study the effect of deprenyl (2.5 mg/kg) injection on synaptophysin and ChAT immunoreactivity. The intraperitoneal injection of deprenyl was done following axotomy and continued for 21 days. Then, the animals were perfused with paraformaldehyde (4%) and spinal cord segment L4-L6 proccessed for immunohistochemistry. The results obtained in this study showed that deprenyl-treated axotomized mice had higher ChAT and synaptophysin expression as compared to untreated axotomized animals.