Diazepam-binding inhibitor and corticotropin-releasing hormone in cerebrospinal fluid

Diazepam-binding inhibitor (DBI) is a neuromodulatory peptide for gamma-aminobutyric acid (GABA) neurotransmission. Cerebrospinal fluid (CSF) levels of DBI have been found to be elevated in depression. CSF levels of the peptide corticotropin-releasing hormone (CRH) have also been found to be elevated in depression. Therefore, we examined for a relationship between DBI and CRH in human CSF. We found significant positive correlations between CSF levels of DBI and CRH in depressed patients, pathological gamblers, and normal controls. These data, along with the elevated CSF levels of DBI in depression, suggest the possibility that DBI may have a role in coordinating responses to stress in humans in addition to its possible role in the pathophysiology of depression.