PAF Receptor Antagonist, ABT-491

An orally available ethynylindole compound that potently inhibits PAF (platelet-activating factor) binding to its receptor in a competitive manner in equilibrium binding studies (K_i = 0.6 or 3.8 nM, respectively, using intact human platelets or isolated rabbit platelet membrane; [PAF] = 0.6 nM), while a non-competitive inhibition is observed if the membrane-bound receptors are pre-incubated with the antagonist prior to the addition of PAF, presumably due to a slower antagonist dissociation rate. Shown to effectively antagonize PAF-induced platelet and neutrophil responses at submicromolar concentrations in vitro and exhibit in vivo efficacy in alleviating PAF-mediated inflammatory and pathological processes in various animals, including guinea pigs, mice, and rats, via either i.v. or p.o.. Reported to display high specificity toward PAF receptor as evaluated in binding assays employing a wide variety of receptors and ion channels.

Packaged under inert gas

Toxicity: Standard Handling (A)

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 3 months at -20°C.

Curtin, M.L., et al. 1998. J. Med. Chem.41, 74.
Albert, D.H., et al. 1998. J. Pharmacol. Exp. Ther.284, 83.
Albert, D.H., et al. 1997. Eur. J. Pharmacol.325, 69.

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany