Although receptors, transporters and channels (RTCs) are key elements in the synaptic membrane, work on analysis and quantification of RTCs by mass spectrometry is limited. Additionally, there is not a single mass spectrometrical study that assigns the localisation of RTCs to the pre- or post-synaptic membrane. Determination of localisation and levels of RTCs in pre- or post-synaptic membranes are essential as RTCs may show different functions in different locations.