TPA-023B GABA-A Modulator: Key Facts & FAQs

TPA-023B is a subtype-selective benzodiazepine site partial agonist acting at GABAA receptors containing alpha2 and alpha3 subunits, widely used as a research tool to dissect anxiolytic and sedative pharmacology.

Chemical Name / Identifier

TPA-023B (systematic name subject to review; CAS number to be confirmed from certificate of analysis)

Primary Target

GABAA receptor, benzodiazepine binding site; selective for alpha2- and alpha3-containing subtypes

Pharmacological Action

Partial agonist at the benzodiazepine site of alpha2/alpha3 GABAA receptors; reduced or absent efficacy at alpha1 and alpha5 subtypes

Research Application

Tool compound for studying anxiolysis without sedation, alcohol interaction studies, and subtype-specific GABA pharmacology

Aladdin SKU

T176460

Recommended Storage

Store as indicated on product datasheet; typically at -20 °C, protected from light and moisture (verify with current CoA)

What Is TPA-023B and How Does It Work?

TPA-023B is a research-grade small molecule that acts as a partial agonist at the benzodiazepine (BZD) binding site of GABA type-A (GABA_A) receptors. Unlike classical benzodiazepines, which potentiate all major GABA_A receptor subtypes indiscriminately, TPA-023B preferentially modulates receptors containing alpha2 (α2) and alpha3 (α3) subunits, with markedly lower or negligible intrinsic efficacy at receptors containing α1 or α5 subunits.

This subtype selectivity is pharmacologically significant because preclinical evidence suggests that anxiolytic activity is primarily mediated through α2- and α3-containing receptors, while sedation and ataxia are more closely linked to α1-containing receptors. By selectively engaging α2/α3 subtypes, TPA-023B serves as a valuable tool for dissecting these distinct pharmacological functions in vitro and in vivo.

Note: Specific binding affinity values (Ki, EC50) and intrinsic efficacy percentages are not reproduced here due to absence in supplied source material; researchers should consult the primary literature and the Aladdin product datasheet (SKU T176460) for precise figures.

Solubility, Formulation, and Handling Guidelines

Proper solubilization is critical for reproducible results with TPA-023B. As with many lipophilic CNS tool compounds, TPA-023B has limited aqueous solubility. The following general guidance applies, but researchers must verify specific solubility data on the current Aladdin product datasheet or certificate of analysis (CoA) for SKU T176460:

• Recommended solvents: Dimethyl sulfoxide (DMSO) is typically used to prepare concentrated stock solutions. Ethanol may also be suitable depending on the application.
• Aqueous dilution: When diluting into aqueous buffers or cell culture media, prepare the final solution stepwise to avoid precipitation. Final DMSO concentration in assay should generally be kept at ≤0.1% to minimise solvent effects.
• Stock solution storage: Aliquot stock solutions and store at -20 °C. Avoid repeated freeze-thaw cycles to preserve compound integrity.
• Light sensitivity: Protect solutions from prolonged light exposure as a precaution.

Always handle TPA-023B following standard laboratory safety practices for research chemicals. Refer to the Safety Data Sheet (SDS) available from Aladdin Scientific prior to use.

Research Applications of TPA-023B

TPA-023B is primarily used as a pharmacological tool compound in preclinical neuroscience and pharmacology research. Key application areas include:

• Anxiolytic mechanistic studies: Investigating whether anxiolytic effects can be achieved via α2/α3-selective GABA_A modulation without the sedative, amnesic, or dependence-related side effects associated with non-selective benzodiazepines.
• Subtype pharmacology: Elucidating the functional roles of individual GABA_A receptor subtypes in neuronal circuits using receptor-subtype-selective ligands.
• Alcohol and drug interaction research: Exploring cross-tolerance and interactions between GABAergic compounds and ethanol at the receptor level.
• In vitro electrophysiology and binding assays: Used in patch-clamp recordings, radioligand competition assays, and fluorescence-based assays to characterise GABA_A receptor function.
• Behavioural pharmacology models: Employed in rodent models of anxiety (e.g., elevated plus maze, fear-potentiated startle) to validate the anxioselective hypothesis.

TPA-023B is intended for research use only and is not approved for human therapeutic use.

Ordering, Availability, and Quality Assurance

TPA-023B is available from Aladdin Scientific under SKU T176460. The following information is relevant for procurement and quality assurance:

• Purity: Aladdin Scientific supplies research-grade reagents with purity specifications confirmed by analytical methods such as HPLC and NMR. Exact purity grade for SKU T176460 should be confirmed on the current product page or CoA.
• Documentation: A certificate of analysis (CoA) and safety data sheet (SDS) are available upon request or via the Aladdin website for each production lot.
• Quantity options: Multiple pack sizes may be available; consult the Aladdin product listing for current stock and pricing.
• Ordering: Orders can be placed directly through the Aladdin Scientific website or by contacting the sales team. For bulk or custom quantities, contact Aladdin customer service.
• Shipping: The compound should be shipped with cold-chain handling as specified in the SDS. Confirm shipping conditions with Aladdin at time of order.

For the most up-to-date availability, pricing, and specification details, visit the Aladdin Scientific product page for SKU T176460.

Frequently asked questions

What is the subtype selectivity profile of TPA-023B at GABAA receptors?

TPA-023B acts as a partial agonist at the benzodiazepine site with preferential activity at GABAA receptors containing α2 and α3 subunits. It displays markedly reduced intrinsic efficacy at α1- and α5-containing receptor subtypes. This selectivity profile makes it useful for studying anxiolytic mechanisms that are potentially separable from sedation. Exact efficacy percentages at each subtype should be verified in the primary literature or the Aladdin product datasheet.

In what solvents can TPA-023B be dissolved for in vitro assays?

TPA-023B is typically dissolved in DMSO to prepare concentrated stock solutions, as it has limited aqueous solubility. The stock solution can then be diluted stepwise into aqueous buffers or cell culture media. Final DMSO concentrations in assay wells should generally be kept at ≤0.1% to avoid solvent-related artefacts. Always verify the specific solubility specification on the current Aladdin CoA for SKU T176460 before preparing solutions.

Is TPA-023B suitable for in vivo studies in rodent models?

Yes, TPA-023B has been used in preclinical in vivo rodent models, particularly in anxiety-related behavioural paradigms such as the elevated plus maze and fear-potentiated startle test, to evaluate the anxioselective hypothesis of α2/α3 GABAA modulation. Appropriate vehicle formulations and dose ranges for in vivo use should be established by the researcher based on the primary literature, as specific in vivo protocols are not provided in this document.

How should TPA-023B be stored to maintain stability?

TPA-023B should be stored according to the conditions specified on the Aladdin product datasheet and CoA for SKU T176460, typically at -20 °C in a dry environment protected from light. Stock solutions in DMSO should be aliquoted to avoid repeated freeze-thaw cycles, which can degrade compound integrity over time. Always check the expiry date on the CoA before use.

Where can I order TPA-023B and what documentation is available?

TPA-023B (SKU T176460) can be ordered directly through the Aladdin Scientific website or via the Aladdin sales team. A certificate of analysis (CoA) and safety data sheet (SDS) are available for each lot. For bulk quantities or custom packaging, contact Aladdin customer service directly. Pricing and stock availability should be confirmed at the time of ordering via the product page.

References

1. Aladdin Scientific product datasheet and certificate of analysis for TPA-023B, SKU T176460. Aladdin Scientific.
2. Atack JR. GABAA receptor subtype-selective modulators. I. alpha2/alpha3-selective agonists as non-sedating anxiolytics. Current Topics in Medicinal Chemistry, 2011. [General reference — specific volume/page details need verification]
3. Rudolph U, Mohler H. GABA-based therapeutic approaches: GABAA receptor subtype functions. Current Opinion in Pharmacology, 2006. [General reference — specific details need verification]

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.