A 438079 is a potent, and selective antagonist of P2X7 receptor (pIC50: 6.9).

P2X7 receptor:6.9(pIC50)

A 438079 在表达大鼠P2X7受体的1321N1细胞中，以321 nM的IC50阻断BzATP-(10 μM)引起的细胞内钙浓度变化。在高达100 μM的浓度下，A 438079对P2X7受体表现出选择性[1]。

在神经病理性大鼠模型中，A 438079 (80 μmol/kg, i.v.) 能够减弱脊髓内不同类神经元由于有害及无害刺激引发的活动，并在SNL及CCI模型中显著提高撤回阈值[1]。与等剂量的苯巴比妥(25 mg/kg)相比，A 438079显示出更优越的神经保护效果[2]。A 438079在一定程度上显著抑制6-OHDA诱导的纹状体DA储存量的损耗[3]。在HC模型中，预先处理A 438079能降低痛觉行为评分[4]。

Human astrocytoma cells, 1321N1, are grown to stably express rat P2X7, human P2X4, P2X2a, P2X2/3, P2X1, P2Y1 and P2Y2 recombinant receptors. Agonist, BzATP, 2,3-O-(4-ben-zoylbenzoyl)-ATP or ATP-induced changes in intracellular Ca2+ concentrations are assessed in all of the cell lines using the Ca2+ chelating dye, Fluo-4, in conjunction with a Fluorometric Imaging Plate Reader. The cells are plated out the day before the experiment onto poly-D-lysine-coated black 96 well plates. After the agonist addition, changes in intracellular Ca2+ concentrations are recorded, per second, for 3 min. Ligands are tested at 11 half-log concentrations from 0.1nM to 100 μM. BzATP or ATP concentrations corresponds to the EC70 values for each receptor to enable comparison of antagonist potencies across the multiple P2 receptor subtypes. A 438079 is added to the cell plate and ?uorescence data are collected for 3 min before the addition of agonist, subsequently, data are then collected for another 2 min. The pEC50 or pIC50 values are derived from a single curve ?t [1].

To confirm A 438079 reach the brain after systemic administration, P10 rat pups are injected with 5 mg/kg A 438079 and killed either 10 min, 30 min, or 2 h later (n=4 per group). Blood samples are centrifuged at 1000×g for 10 min to isolate the plasma. Samples are analyzed using LC-MS/MS by a service provider. Briefly, protein is precipitated from 50 μL aliquots of the individual plasma or brain tissue homogenate, and A 438079 is quantified by LC-MS/MS from a five-point standard curve [2].