Serotonin and the Stress Cascade

The adrenal glands have receptors for serotonin and they're very sensitive to it. Even in the absence of your brain You can actually get the stress reaction Simply by elevating serotonin or providing it in the milieu where the where the adrenal cells are. Cortisol rises as soon as you inject serotonin, which is not a coincidence that serotonin antagonist such as cyprohectidine are actually used successfully for treating Cushing syndrome.