Behavioral studies have suggested an involvement of the glutamate pathway in the mechanism of action of anxiolytic drugs, including the NMDA receptor complex. It was shown that magnesium, an NMDA receptor inhibitor, exhibited anxiolytic-like activity in the elevated plus-maze test in mice. The purpose of the present study was to examine interaction between magnesium and benzodiazepine/GABA(A) r...

CLINICAL PHARMACOLOGY Lorazepam interacts with the γ-aminobutyric acid (GABA)-benzodiazepine receptor complex, which is widespread in the brain of humans as well as other species. This interaction is presumed to be responsible for lorazepam’s mechanism of action. Lorazepam exhibits relatively high and specific affinity for its recognition site but does not displace GABA. Attachment to the speci...

Central and peripheral benzodiazepine receptors were localized in the rat, monkey, and human eye by in vitro autoradiography. Central benzodiazepine binding sites, visualized with 3H-R015-1788, were enriched in the inner plexiform layer in all three species. Binding sites also were present in the nerve fiber layer, the ganglion cell layer, and in portions of the inner nuclear layer. Peripheral ...

Ligands of the benzodiazepine binding site allosterically modulate g-aminobutyric acidA receptors. Their binding pocket is made up of amino acid residues located on both a and g subunits. We transiently expressed wild-type a1b2g2 and mutant GABAA receptors in human embryonic kidney 293 cells and determined their binding properties. Receptors containing the mutant aY209A showed ;40-fold decrease...

Sir,—We read with interest the study by Takada and colleagues [1] on the effects of midazolam and flunitrazepam on the release of dopamine from rat striatum. Recently, we postulated that benzodiazepines may reduce the synthesis, release and postsynaptic effect of dopamine centrally [2]. This action at the chemoreccptor trigger zone is a possible mechanism for the antiemetic effect of benzodiaze...

Two endogenous ligands for the brain benzodiazepine-binding sites were isolated from bovine brain through gel filtration, paper electrophoresis, and paper chromatography. These ligands were identified as inosine and hypoxanthine, and both had a higher affinity for the brain benzodiazepine-binding sites than for benzodiazepine sites in some peripheral tissues. They did not bind to any other rece...

To the Editor: In the April 2012 issue of the Journal, Kao et al1 examined the possible relationship between benzodiazepine use and cancer risk. While increased mortality with benzodiazepine use has been demonstrated in several studies, studies examining the association between cancer and benzodiazepine use have yielded conflicting results.2–6 Kao et al have attempted to demonstrate a possible ...

The pattern of all index admissions for benzodiazepine self-poisoning to a university hospital in Karachi, Pakistan are described. Of the 329 medication self-poisoning cases, 84% were benzodiazepine overdoses. Diazepam was the preferred drug in 69% of these cases, with majority ingesting between 20-30 tablets of 5 mg each, 44% bought the benzodiazepine over the counter (OTC) for the purpose of ...

Separate sub-populations of benzodiazepine receptors are involved in determining hippocampal theta frequency in freely moving rats. Systemic injection of the benzodiazepine chlordiazepoxide (CDP) reduced the frequency of theta elicited by stimulation of the brainstem reticular formation, and theta recorded during fixed interval (FI) bar pressing. Infusion of the benzodiazepine receptor antagoni...

From three general practices, served by 11 principals, 205 long-term benzodiazepine users were identified and matched for age and sex with controls. Benzodiazepine users had significantly higher rates of previous physical illness, consultation and non-psychotropic drug consumption than controls. The characteristics of those receiving prescriptions for benzodiazepine hypnotics alone, anxiolytics...