Abstract：Objective The aim of this study is to explore the effects of manganese (Mn) exposure for different time on synaptic vesicle and its associated proteins in neurons. Methods After the primary cultured neurons in vitro were treated with Mn (100μM) for 0,6,12,18 or 24 hours, the cell viability and LDH release in culture medium were detected. The expression of soluble NSF accessory protein receptor(SNARE) complex gene and protein and the number of active synaptic vesicles were determined. Results With the increase of Mn exposure time, neuronal cell damage gradually aggravated(P<0.01). Compared with the control group, syntaxin 1A gene and protein expression in the Mn exposed cells showed no significant changes (P>0.05). Synaptosome-associated protein of 25 kDa (SNAP 25) gene and protein expressions were gradually decreased with exposure time (P<0.05), while vesicle-associated membrane protein 2(VAMP 2)gene and protein expressions were gradually increased (P<0.01), which led to first increase and then decrease of the formation of SNARE complex. At the same time, the release of active synaptic vesicles changed accordingly. Conclusions Mn disturbs the expressions of SNARE complex relevant proteins and reduces the formation of the SNARE complex in a time-dependent manner, which leads to reduction of activity of synaptic vesicles and to neurotransmitter release disorders.
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2016, Vol. 23 
