Updated project metadata. 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.