Ro 61-8048 is a potent and selective inhibitor of kynurenine hydroxylase with IC50 of 37 nM.IC50 value: 37 nM [1]Target: kynurenine hydroxylase inhibitorin vitro:in vivo: Ro 61-8048 blocked rat and gerbil kynurenine 3-hydroxylase after oral administration, with ED50's in the 3-5 mumol/kg range in gerbil brain. In a microdialysis experiment in rats, 16 dose dependently increased kynurenic acid concentration in the extracellular hippocampal fluid. A dose of 100 mumol/kg po led to a 7.5-fold increase in kynurenic acid outflow [1]. A significant reduction in infarct volumes also was found when the kynurenine hydroxylase inhibitors were given to rats after permanent middle cerebral artery occlusion (from 207+/-111 mm3 in vehicle-treated rats to 82+/-18 and to 62+/-57 mm3 in rats treated with mNBA, 400 mg/kg intraperitoneally, or with Ro 61-8048, 40 mg/kg intraperitoneally, respectively) [2]. intrastriatal injections of Ro 61-8048 (60-80 microg/hemisphere) significantly reduced the severity of dystonia in dt(sz) hamsters [3].
References:
[1]. Rover S, et al. Synthesis and biochemical evaluation of N-(4-phenylthiazol-2-yl)benzenesulfonamides as high-affinity inhibitors of kynurenine 3-hydroxylase. J Med Chem. 1997 Dec 19;40(26):4378-85.
[2]. Cozzi A, et al. Kynurenine hydroxylase inhibitors reduce ischemic brain damage: studies with (m-nitrobenzoyl)-alanine (mNBA) and 3,4-dimethoxy-[-N-4-(nitrophenyl)thiazol-2yl]-benzenesulfonamide (Ro 61-8048) in models of focal or global brain ischemia. J C
[3]. Hamann M, et al. Effects of the kynurenine 3-hydroxylase inhibitor Ro 61-8048 after intrastriatal injections on the severity of dystonia in the dt sz mutant. Eur J Pharmacol. 2008 May 31;586(1-3):156-9.