In the central nervous system, 5-HT1D is expressed in the basal ganglia, hippocampus and cortex in rat and in the basal ganglia, midbrain and spinal cord in human. In serotonin neurons, 5-HT1D receptors are autoreceptors thereby inhibiting the release of 5-HT. In GABA, ACh, and glutamate neurons they are heteroreceptors where they control the release of these neurotransmitters.nAs mentioned above, the serotonin system plays an undeniable role in the perception and processing of pain. Indeed, many migraine sufferers are prescribed triptan-based drugs which activate 5-HT1B and 5-HT1D receptors
