TNP-ATP (sodium salt)

TNP-ATP is a derivative of ATP and an antagonist of the purinergic P2Y₁, P2X₃, and P2X_2/3 receptors (IC₅₀s = 6, 0.9, and 7 nM, respectively, in HEK293 cells expressing the human receptors).¹ It is selective for these receptors over the purinergic P2X₂, P2X₄, and P2X₇ receptors (IC₅₀s = 2, 15.2, and >30 µM, respectively, in HEK293 cells expressing the human receptors). TNP-ATP decreases acetic acid-induced calcium flux in 1321N1 cells expressing the P2X₃ and P2X_2/3 receptors (IC₅₀s = 100 and 62 nM, respectively).² It reduces acetic acid-induced writhing in a mouse model of visceral pain (ED₅₀ = 6.35 µmol/kg). It displays excitation/emission maxima of 403 and 547 nm, respectively, and its relative fluorescence increases four-fold when bound to insulin-degrading enzyme (IDE) with an emission maximum of 538 nm.³