Medical Condition:
Protein P38, Synaptic Vesicle
A 38-kDa integral membrane glycoprotein of the presynaptic vesicles in neuron and neuroendocrine cells. It is expressed by a variety of normal and neoplastic neuroendocrine cells and is therefore used as an immunocytochemical marker for neuroendocrine differentiation in various tumors. In ALZHEIMER DISEASE and other dementing disorders, there is an important synapse loss due in part to a decrease of synaptophysin in the presynaptic vesicles.