How SSRIs Work
Dude, you guys need to stop me from going almost a full month without submitting anything…. Anyway, here’s some facts. The cartoon’s pretty vague so an explanation’s below; I’m basing this mostly off my time in ze lab so you may want to Wikipedia this before quoting me everywhere.
Say you’ve got the 1C pathway, where serotonin’s going from one group of neurons (let’s call it A) to another (B). If B is lacking receptors for serotonin, then you end up with serotonin floating around in the extracellular space–but it doesn’t stay there long. Reuptake mechanisms come by to grab the extra serotonin and whisk it off somewhere else (where, I don’t remember; I think it depends, though). In short, the pathway’s ineffectual because while serotonin’s going from A to B, C (the consequence of B being activated) isn’t happening.
Panel 1 – Selective serotonin reuptake inhibitors do exactly what they sound like. They stop the reuptake mechanism from yoinking the serotonin.
Panel 2 – This leads to more serotonin in the extracellular space. But it can’t float around there forever….
Panel 3 – So the cells in B start growing more serotonin receptors, which leads to more efficient uptake of serotonin, strengthening the connections between the pathways. More impulses are getting through, which means happytimes, as long as the right pathway’s being influenced! (This is one reason why the selectivity’s become a big deal: less side effects. Of course it doesn’t work on as many people, but there are a ton of pathways out there. Someday, y’know?
Anyway, the big problem with this explanation is that there’s about a two- to three-week delay before SSRIs start showing behavioral improvements. But that’s why I have to go study brains!