HTR1A and major depressive disorder: Importantly, CBD reversed the increased expression of miR-16 and miR-135 and the decrease in the 5-HT1A receptor gene in the ventromedial prefrontal cortex (vmPFC) in rats subjected to UCMS.35 Previous studies showed that miR-16 and miR-135 could be used as biomarkers for the diagnosis of depression.125