The researchers administered an SSRI, a common type of antidepressant that’s thought to work by increasing the brain’s low serotonin levels. The new work shows the antidepressant appears to have other important effects. When administering SSRIs, the team saw that the drug first collected in the lipid rafts, and afterward, the critical GαS protein moved out of the rafts, freeing it up and making the protein more effective. This physical delay in the cells corresponded to the therapeutic delay of antidepressants.
Mark Rasenick, an author of the study and a physiologist at UIC, sees these findings as more than just an explanation for antidepressants’ lag time. He says he plans to use these findings to develop a test to help predict how patients will respond to an antidepressant.