Considering that CgA is stored and coreleased with serotonin and other catecholamines by cells of the neuroendocrine system [30], the increased circulating levels of CgA observed in MD patients referring with a high number of vertigo spells in the last month may be related to activation of the autonomic system (in which serotonin has been demonstrated to be an important neurotransmitter) consequent to vestibular overloading [31]. This evidence concerns the gene CGA and Menkes disease.