The symptomatology characterizing fibromyalgia (FM) comprises
three systems: the musculoskeletal system with widespread muscular
pain, neuroendocrine disorders, and psychological distress including
depression. Though the most prominent symptom of FM is pain
in defined points of the musculoskeletal system, the numerous
other somatoform and psychological disorders suppose a common
primary disturbance which we consider to originate within higher
levels of the central nervous system. Recent studies of the
entire endocrine profile of FM patients following a simultaneous
challenge of the hypophysis with corticotropin-releasing hormone
(CRH), thyrotropin-releasing hormone, growth hormone-releasing
hormone, and luteinizing hormone-releasing hormone support the
hypothesis that an elevated activity of CRH neurons determines
not only many symptoms of FM but may also cause the deviations
observed in the other hormonal axes. Hypothalamic CRH neurons
thus may play a key role not only in "resetting" the various
endocrine loops but possibly also nociceptive and psychological
mechanisms as well.
