High throughput functional assays for P2X receptors.

Area of Science:

• Neuroscience
• Pharmacology
• Cell Biology

Background:

• Adenosine triphosphate (ATP) is a key signaling molecule that activates purinergic receptors, including ionotropic P2X receptors.
• P2X receptors are nonselective cation channels crucial for neuronal excitability, glial function, and smooth muscle contraction.
• These receptors are implicated in various physiological and pathological processes, making them targets for therapeutic intervention.

Purpose of the Study:

• To provide robust protocols for the pharmacological evaluation of ligands targeting P2X receptors.
• To detail methods for assessing P2X receptor activation in both native and recombinant cell systems.
• To enable the characterization of different P2X receptor subtypes, including their desensitization kinetics and pore-forming capabilities.

Main Methods:

• Calcium imaging techniques are described for the pharmacological characterization of P2X receptors, distinguishing between fast and slowly desensitizing subtypes.
• Protocols are provided for measuring the activation of homomeric P2X3 and heteromeric P2X2/3 receptors.
• A specific protocol is included for assessing P2X7 receptor-mediated pore formation in THP-1 cells.

Main Results:

• The described calcium imaging methods effectively characterize the pharmacological profiles of various P2X receptor subtypes.
• The protocols allow for the differentiation of fast (P2X3) and slow (P2X2/3) desensitizing P2X receptors.
• The P2X7 receptor pore formation assay provides a means to study this specific receptor subtype in a relevant cellular context.

Conclusions:

• The provided experimental protocols are valuable tools for researchers studying P2X receptor pharmacology.
• These methods facilitate the discovery and development of novel P2X receptor modulators.
• The assays are adaptable for studying a wide range of P2X receptor subtypes and their functions.