Endogenous benzodiazepine receptor ligands in idiopathic recurring stupor.
"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.
Rothstein
J D
JD
Department of Neurology, Johns Hopkins University, Baltimore, Maryland 21205.
Guidotti
A
A
Tinuper
P
P
Cortelli
P
P
Avoni
P
P
Plazzi
G
G
Lugaresi
E
E
Schoch
P
P
Montagna
P
P
D000328:Adult; D000368:Aged; D002851:Chromatography, High Pressure Liquid; D003128:Coma / Q000097:blood / Q000134:cerebrospinal fluid / Q000188:drug therapy; D026261:Diazepam Binding Inhibitor; D004569:Electroencephalography; D005069:Evaluation Studies as Topic; D005442:Flumazenil / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000097:blood / Q000134:cerebrospinal fluid / Q000502:physiology; D006180:Proton-Translocating ATPases; D011869:Radioligand Assay; D011963:Receptors, GABA-A / Q000187:drug effects; D012008:Recurrence
D026261:Diazepam Binding Inhibitor; D009419:Nerve Tissue Proteins; D011963:Receptors, GABA-A; D005442:Flumazenil; D006180:Proton-Translocating ATPases