Think of intercellular communication between cells in brains along the lines of how language itself works.
Our “neurotransmitters” work very similarly to “language” as a whole, e.g. GABA being “English”, and Glu being “Spanish”, and Serotonin being “French” or whatever languages you prefer if you aren’t in North America.
They provide the baseline structure and context for communication, and while most cells only speak one language, some cells speak multiple languages.
Think of peptides (e.g. the Neuroligins) as actual words. These words don’t have meaning in and of themselves, however when paired with a language they gain discrete context for each language.
Multiple peptides can be expressed to create more complicated signalling constructs (like sentences), and these signalling constructs take on context local to the cells (think of this as a “dialect”).
In order for the word to have meaning, both the transmitting cells and receiving cells need to understand the word in the same context (e.g. need to have the same receptors expressed and bound to a similar/same stimuli response).
Think of astrocytes as “teacher” cells, they listen to incoming language and physically reprogram other cells to add new words (express specific receptors) to their vocabulary, and also dictate the context with which the words are used.
Does this make sense?
Edit: Neuroligin isn’t the best example here, but still works. Trying to figure out a way to express neurotransmitters as a sort of “volume/loudness” transmitter, while the actual “data” which doesn’t actually transmit information in and of itself. Maybe saying neurotransmitters modulate the sensitivity of other cells to messages represented by peptide/protein transmission?
When we “increase dopamine” for example, dopamine doesn’t in and of itself encode any data at all, other than signal the strength of signal along that pathway. High dopamine levels make communicating cells more sensitive to those messages, however unless there’s an accompanying peptide/protein burst associated, it’s just an empty transmission.
The overarching conceit is that if we can figure out what the RNA expression looks like intercellularly (by reading the peptides being expressed by the astrocytes controlling the synaptic gaps), we can mimic any “natural” cellular messaging process, from inducing apoptosis to re-writing a memory.
I think I used neuroligin here because I think it’s an important peptide that induces the actin dynamics necessary to induce a type of “write mode”/synaptogenesis, which we can use to manipulate encoding of information. I suppose this sounds a lot like the ultimate goal of many nootropics regimes, just far more specifically targeted to the individuals own construction.