Ifenprodil is a selective NMDA receptor (glutamate) antagonist.

NMDAR:0.3 μM

Ifenprodil inhibits NMDA-induced currents at both 10 μM and 100 μM, with IC50 values of 0.88 μM and 0.17 μM, respectively. In rat cortical neurons, Ifenprodil (10 μM) suppresses the majority of currents elicited by NMDA receptors.

In vitro biochemical and pharmacological assaysinhibition studies with recombinant human COX-1 and COX-2: Microsomal preparations of recombinant human COX-1 and COX-2 are prepared from a vaccinia virus-COS-7 cell expression system. Recombinant human COX-1 and COX-2 are expressed in baculovirus-Sf9 cells, and enzymes are purified. Enzymatic activity is monitored continuously by either a fluorescence assay measuring the appearance of the oxidized form of the reducing agent cosubstrate homovanillic acid or by oxygen consumption. The HPLC assay for the assessment of inhibition of purified COX-1 by Rofecoxib with 0.1 μM arachidonic acid substrate concentration, the determination of the stoichiometry of the complex between COX-2 and Rofecoxib, the dissociation rate constant of the enzyme-inhibitor complex by recovery of enzymatic activity, and the recovery of intact Rofecoxib from that complex are all performed as described previously. The solvent system for the HPLC analysis of Rofecoxib is 15:85 MeOH/aqueous potassium phosphate (1 g/liter), with elution by a linear gradient of 15 to 75% MeOH over 25 minutes with detection at 275 nm on a Novapak C18 column.