Palonosetron N-oxide is a metabolite of the serotonin (5-HT) receptor subtype 5-HT3antagonist palonosetron .1It is also a potential impurity in palonosetron preparations.2Palonosetron N-oxide is a degradation product formed by exposure to oxidative stress. 1.Stoltz, R.A., Cyong, J.-C., Shah, A., et al.Pharmacokinetic and safety evaluation of palonosetron, a 5-hydroxytryptamine-3 receptor antagonist, in U.S. and Japanese healthy subjectsJ. Clin. Pharmacol.44(5)520-531(2004) 2.Vishnu Murthy, M., Srinivas, K., Kumar, R., et al.Development and validation of a stability-indicating LC method for determining palonosetron hydrochloride, its related compounds and degradation products using naphthalethyl stationary phaseJ. Pharm. Biomed. Anal.56(2)429-435(2011)

5-HT3 antagonist 5 is a quinoxalin-2-carboxamide compound which is a 5-HT 3 receptor antagonist. 5-HT3 antagonist 5 exerts antagonism on 5-HT 3 agonist and 2-methyl-5-HT, and exhibits anti-depressant effect in mice [1].

Indisetron Dihydrochloride is a 5-HT(3) and 5-HT(4) receptor antagonist. Indisetron reduces 2-methyl-5-serotonin (HT)-induced bradycardia.

Ensaculin is a NMDA antagonist and a 5HT1A agonist potentially for the treatment of Alzheimer's disease (AD). Ensaculin showed memory-enhancing effects in paradigms of passive and conditioned avoidance in both normal and artificially amnesic rodents. It e

Indisetron is a 5-HT(3) and 5-HT(4) receptor antagonist. Indisetron reduces 2-methyl-5-serotonin (HT)-induced bradycardia.

Eltoprazine(DU28853) is a serenic or antiaggressive agent which as an agonist at the 5-HT1A and 5-HT1B receptors and as an antagonist at the 5-HT2C receptor.IC50 value:Target: 5-HT1A/1B agonist; 5-HT2C antagonistin vitro: The binding of [3H]eltoprazine to whole tissue sections was saturable and revealed an apparent dissociation constant (Kd) of 11 nM. Specific [3H]eltoprazine binding was completely displaced by 5-HT; conversely, unlabelled eltoprazine reduced [3H]5-HT binding to the levels of non-specific binding [1]. Eltoprazine evoked membrane changes that were similar to but much weaker than those induced by 5HT. Both the 5HT- and eltoprazine-evoked membrane hyperpolarizations were largely suppressed in the presence of spiperone [2].in vivo: eltoprazine is extremely effective in suppressing dyskinesia in experimental models, although this effect was accompanied by a partial worsening of the therapeutic effect of l-dopa. Interestingly, eltoprazine was found to (synergistically) potentiate the antidyskinetic effect of amantadine. The current data indicated that eltoprazine is highly effective in counteracting dyskinesia in preclinical models [3]. Rats were chronically treated with mianserin (10 mg/kg i.p.) or eltoprazine (1 mg/kg i.p.) and were tested in the elevated plus-maze test for anxiety. Mianserin and eltoprazine displayed opposite effects in the elevated plus-maze: mianserin induced anxiolytic-like effects, while eltoprazine showed anxiogenic-like ones [4]. [1]. Sijbesma H, et al. Eltoprazine, a drug which reduces aggressive behaviour, binds selectively to 5-HT1 receptor sites in the rat brain: an autoradiographic study. Eur J Pharmacol. 1990 Feb 20;177(1-2):55-66. [2]. Joels M, et al. Eltoprazine suppresses hyperpolarizing responses to serotonin in rat hippocampus. J Pharmacol Exp Ther. 1990 Apr;253(1):284-9. [3]. Bezard E, et al. Study of the antidyskinetic effect of eltoprazine in animal models of levodopa-induced dyskinesia. Mov Disord. 2013 Jul;28(8):1088-96. [4]. Rocha B, et al. Chronic mianserin or eltoprazine treatment in rats: effects on the elevated plus-maze test and on limbic 5-HT2C receptor levels. Eur J Pharmacol. 1994 Sep 1;262(1-2):125-31.