Endogenous benzodiazepine receptor ligands in idiopathic recurring stupor

Lancet. 1992 Oct 24;340(8826):1002-4. doi: 10.1016/0140-6736(92)93011-b.


"Endozepines" are endogenous ligands for the benzodiazepine recognition sites on gamma-aminobutyric acid A receptors in the nervous system. Idiopathic recurring stupor (IRS) is a syndrome of spontaneous stupor or coma that is not associated with known metabolic, toxic, or structural abnormalities but can be reversed by flumazenil, a pure benzodiazepine antagonist. We measured endozepine-2 and endozepine-4 by high-performance liquid chromatography and radioreceptor assay in serum and cerebrospinal fluid from three patients with IRS. During episodes of stupor there was a large (up to 300-fold compared with control patients) increase of endozepine-4 content in cerebrospinal fluid and serum, but a return to normal concentrations between attacks. Endozepine-4 may contribute to, or be the cause of, IRS. The reasons for abnormal concentrations of endozepine in blood and brain are unknown.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aged
  • Chromatography, High Pressure Liquid
  • Coma* / blood
  • Coma* / cerebrospinal fluid
  • Coma* / drug therapy
  • Diazepam Binding Inhibitor
  • Electroencephalography
  • Evaluation Studies as Topic
  • Flumazenil / therapeutic use
  • Humans
  • Male
  • Middle Aged
  • Nerve Tissue Proteins* / blood
  • Nerve Tissue Proteins* / cerebrospinal fluid
  • Nerve Tissue Proteins* / physiology
  • Proton-Translocating ATPases
  • Radioligand Assay
  • Receptors, GABA-A* / drug effects
  • Recurrence


  • Diazepam Binding Inhibitor
  • Nerve Tissue Proteins
  • Receptors, GABA-A
  • Flumazenil
  • Proton-Translocating ATPases