Research Article

Effects of a Proprietary Standardized Orthosiphon stamineus Ethanolic Leaf Extract on Enhancing Memory in Sprague Dawley Rats Possibly via Blockade of Adenosine A2A Receptors

Figure 4

Response curve for adenosine A2A antagonist assay. The IC50 of adenosine A2A antagonist assay for O. stamineus ethanolic extract is 51.5 μg/mL.