Dr Katalin Tóth and her team recently published a paper in Nature Communications in which they explain, in part, how seemingly identical synaptic vesicles can be used to transmit different messages from one neuron to the next.
These researchers showed that vesicles derived from the AP-3-dependent endocytotic pathway were preferentially used in asynchronous release of neurotransmitter, a process involved in transmission of information between specific brain regions important for processing spatial information. They also showed that animals lacking the AP-3-dependent recycling pathway had altered synaptic transmission in naturally occuring processes.
Read more in the original research article:
Evstratova A, Chamberland S, Faundez V, Tóth K. Vesicles derived via AP-3 dependent recycling contribute to asynchronous release and influence information transfer. Nature Communications, 2014 November 20 5:5530. doi: 10.1038/ncomms6530.