Abstract
Interactions of GABA, bicuculline methochloride and diazepam with [3H]TBOB binding to rat brain membranes were evaluated in vitro. GABA displaced [3H]TBOB binding with and IC50 of 4 microM and a slope factor near unity. The competitive GABA antagonist bicuculline methochloride shifted the displacement curve of GABA parallelly to the right, indicating that the interaction of GABA with [3H]TBOB binding is of an allosteric nature. In the presence of GABA, diazepam displaced the binding of [3H]TBOB according to a two-site model: a high affinity site with an IC50 of about 50 nM and a lower affinity site with an IC50 of about 30 microM. Bicuculline methochloride abolished the nanomolar displacement by diazepam and increased the micromolar IC50 value. These results indicate that the interaction of the high affinity diazepam site with the [3H]TBOB binding site is totally GABA dependent and that the low affinity effect of diazepam on [3H]TBOB binding is at least partially GABA dependent. It is likely that the low affinity potency of diazepam to displace [3H]TBOB binding has physiological relevance.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
