Do serotonergic neurons throughout the brainstem share a role as CO2 / pH sensors?
Since the majority (>90%) of serotonergic neurons in the medulla are stimulated by acidosis, some of these neurons must project to nonrespiratory nuclei. If this is the case, then what do these neurons do? How does this relate to the fact that the majority of serotonergic neurons in the midbrain are also chemosensitive? Many of the neural systems influenced by serotonergic neurons are also sensitive to changes in blood CO2, so it is reasonable to suppose that serotonergic neurons mediate nonrespiratory effects of increased CO2. Our hypothesis is that chemosensitive serotonergic neurons induce a variety of downstream effects aimed at restoring pH homeostasis in response to a CO2 challenge, including increased ventilation, changes in autonomic output, arousal, anxiety and altered cerebrovascular flow. Serotonin and human disease There are many human diseases that are linked to serotonin. These include sleep apnea, panic disorder, epilepsy, migraine, and SIDS. Interestingly, each of these
