Abstract
Light microscopic evidence suggested a synaptic role for agmatinase, an enzyme capable of inactivating the putative neurotransmitter and endogenous anti-depressant agmatine. Using electron microscopy and an alternative pre-embedding approach referred to as virtual pre-embedding, agmatinase was localised pre- and postsynaptically, to dendritic spines, spine and non-spine terminals, and dendritic profiles. In dendritic spines, labelling displayed a tendency towards the postsynaptic density. These results further strengthen a synaptic role for agmatine and strongly suggest a regulatory role for synaptically expressed agmatinase.
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We gratefully acknowledge the technical assistance of Berit Söhl-Kielczynski.
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Madai, V.I., Poller, W.C., Peters, D. et al. Synaptic localisation of agmatinase in rat cerebral cortex revealed by virtual pre-embedding. Amino Acids 43, 1399–1403 (2012). https://doi.org/10.1007/s00726-011-1195-5
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DOI: https://doi.org/10.1007/s00726-011-1195-5