Biological Activity
Preladenant is a potent and competitive antagonist of the human adenosine A2A receptor with a Ki of 1.1 nM and has over 1000-fold selectivity over other adenosine receptors.
In Vitro
Preladenant also completely antagonizes cAMP in cells expressing the recombinant human A2A receptor. Preladenant is determined to has KB values of 1.3 nM at the A2A receptor; the value is in good agreement with the Ki value determined in the radioligand binding assay. A similar functional assay with A2B receptor-expressing cells is used to demonstrate selectivity over A2B receptors. In this assay, the KB value for Preladenant is 1.2 μM, indicating that Preladenant is 923-fold selective for the A2A receptor over the A2B receptor[1].
In Vivo
Preladenant (1 mg/kg) inhibits L-Dopa-induced behavioral sensitization after repeated daily administration, which suggests a reduced risk of the development of dyskinesias. Preladenant exhibits antidepressant-like profiles in models of behavioral despair, namely the mouse tail suspension test and the mouse and rat forced swim test[1]. Preladenant produces a dose-dependent reduction in parkinsonian scores at doses of 1 mg/kg (min score: 9.0) and 3 mg/kg (min score: 6.5). A subthreshold dose of Preladenant reduces minimum and mean parkinsonian scores in animals treated with 3 mg kg of L-Dopa to 5.25 and 6.88 respectively. A Wilcoxin test is used to compare individual treatments against vehicle. Preladenant (3 mg/kg), L-Dopa (3, 6, and 12 mg/kg), and the combination of Preladenant and L-Dopa (1 or 3 mg/kg+3 mg/kg) are all significantly improved on the minimum parkinsonian score. In addition, both the 12 mg/kg L-Dopa and L-Dopa+Preladenant groups are significantly improved on both minimum and mean parkinsonian scores relative to the 3 mg/kg L-Dopa group[2].
References & source
Published experimental findings depend on the model and assay conditions. They do not guarantee equivalent performance in every application. For laboratory research use only.