5-ht-3 antagonist 1

5-HT3 antagonist 1 is a potent and selective inhibitor of the 5-HT3 receptor.

Litoxetine HCl is a selective 5-hydroxytryptamine (5-HT) reuptake inhibitor (SSRI) and mixed 5-hydroxytryptamine antagonist used in the treatment of urinary incontinence. Litoxetine HCl in the absence of antimuscarinic concentrations without antimuscarinic properties (10 nM-1 microM) caused concentration-dependent relaxation of isolated oesophageal muscle mucosa in rats, reducing carbachol tone by up to 37%. Higher concentrations of Litoxetine HCl (3 microM-300 microM) were associated with significant relaxation up to abolition of carbachol tone. The antiarrhythmic activity of Litoxetine HCl, previously demonstrated in the isolated guinea pig intestine, was exerted in the isolated rat oesophageal muscle mucosa at concentrations greater than 1 microM. The 5-HT-releasing effect of Litoxetine HCl could explain the potency of Litoxetine HCl on 5-HT-induced relaxation in untreated rat tissue, which was reversed by pCPA treatment.

5-HT3 antagonist 5 is a quinoxalin-2-carboxamide compound that acts as a 5-HT3 receptor antagonist, counteracting 5-HT3 agonist and 2-methyl-5-HT, and demonstrating an anti-depressant effect in mice [1].

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

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)

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.

Scopolamine is a high-affinity (nanomolar level) muscarinic receptor antagonist that can reversibly inhibit 5-HT₃ receptor responses (IC₅₀ = 2.09 μM). It is commonly used to induce animal models of Alzheimer's disease or memory impairment.