AAT Bioquest

Are there any substitutes for probenecid in calcium assays?

Posted February 2, 2024


Sulfinpyrazone is a commonly used alternative for probenecid in calcium assays. It is an alternative blocker of anion transport and has shown significant improvement in indicator dye loading and widening the screening window. However, it has no impact on the effectiveness of agonists and does not activate TRPA1 (Transient Receptor Potential Ankyrin 1). Additionally, experiments have shown that sulfinpyrazone may also hinder P2X7 responses. Another substitute for probenecid in calcium assays is 2-aminoethoxydiphenyl borate. 2-aminoethoxydiphenyl borate is an effective inhibitor of store-operated calcium entry, but its effectiveness as an inhibitor of inositol trisphosphate (InsP3)-induced calcium release is comparatively lower.

Additional resources

TRPA1 agonist activity of probenecid desensitizes channel responses: consequences for screening

Calcium Indicators

Cal-520®, AM