RWJ-52353 hydrochloride is an orally potent, highly selective α2D adrenergic receptor agonist (Ki: 1.5 nM) with potential analgesic effects. RWJ-52353 hydrochloride demonstrated analgesic activity in abdominal tests in rats and mice, and improved agitation in mice in the hot plate test and tail flick test. RWJ-52353 hydrochloride also regulates the organic cation transporter (OCT) subtype, inhibiting rOCT1 and rOCT2 with IC₅₀s of 100 μM and 20 μM respectively; it also activates rOCT3, affecting [3H]-1- in cells. Methyl-4-phenylpyridinium ([3H]MPP) transport^[1][2].