NMDA Receptor

(1S,2S)-1-(4-Hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidino)-1-propanol (20, CP-101,606) has been identified as a potent and selective N-methyl-D-aspartate (NMDA) antagonist through a structure activity relation (SAR) program based on ifenprodil, a known antihypertensive agent with NMDA antagonist activity. Sites on the threo-ifenprodil skeleton explored in this report include the pendent methyl group (H, methyl, and ethyl nearly equipotent; propyl much weaker), the spacer group connecting the C-4 phenyl group to the piperidine ring (an alternating potency pattern with 0 and 2 carbon atoms yielding the greatest potency), and simple phenyl substitution (little effect). While potent NMDA antagonists were obtained with a two atom spacer, this arrangement also increased alpha 1 adrenergic affinity. Introduction of a hydroxyl group into the C-4 position on these piperidine ring resulted in substantial reduction in alpha 1 adrenergic affinity. The combination of these observations was instrumental in the discovery of 20. This compound potently protects cultured hippocampal neurons from glutamate toxicity (IC50 = 10 nM) while possessing little of the undesired alpha 1 adrenergic affinity (IC50 approximately 20 microM) of ifenprodil. Furthermore, 20 appears to lack the psychomotor stimulant effects of nonselective competitive and channel-blocking NMDA antagonists. Thus, 20 shows great promise as a neuroprotective agent and may lack the side effects of compounds currently in clinical trials[1].

Effectively blocking the NMDA (ip)-stimulated induction of anesthetic cfos is Traxoprodil at 1 mg/kg [1]. At dosages of 20 and 40 mg/kg, tranprodil demonstrated antidepressant efficacy in the forced swim test and was linked to alterations in animal locomotion [2]. PTZ (70 mg/kg; i.p.) increases systemic tonic tetanes when tranprodil (20 nM icv) is administered. The total predicted benefit time is shortened and the possible period of tetanic recovery and fullness is prolonged when tracoprodil (60 mg/kg, coal) is used[3].

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Traxoprodil (20 nM icv) increases systemic tonic tetanes induced by PTZ (70 mg/kg; i.p.); Traxoprodil (60 mg/kg, coal) prolongs the potential period of tetanic recovery and fullness and reduces the total expected benefit time[3]. Traxoprodil demonstrated antidepressant activity in the forced swim test at doses of 20 and 40 mg/kg and was associated with changes in animal locomotion [2].

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Polyamines, including spermidine, facilitate seizures by positively modulating N-methyl-d-aspartate receptors (NMDAr). Although NMDAr antagonists decrease seizures, it remains to be determined whether traxoprodil, a selective antagonist at the NR2B subunit of the NMDAr, decreases seizures and whether spermidine facilitates pentylenetetrazol (PTZ)-induced seizures. Adult male Wistar rats were injected in the lateral ventricle with 0.9% NaCl (1μl, i.c.v.), spermidine (0.02, 0.2 or 2nmol/site, i.c.v.) or traxoprodil (0.2, 2 or 20nmol, i.c.v.) and with PTZ (35 or 70mg/kg, i.p.). The effect of orally administered traxoprodil (60mg/kg, p.o.) on seizures was also investigated. Latencies to clonic and generalized seizures, as well the total time spent in seizures were recorded by behavioral and electrographic methods (EEG). Spermidine (2nmol/site; i.c.v.) facilitated the seizures induced by a sub-threshold dose of PTZ (35mg/kg; i.p.), but did not alter seizure activity induced by a convulsant dose of PTZ (70mg/kg; i.p.). Traxoprodil (20nmol i.c.v.) increased the latency to generalized tonic-clonic seizures induced by PTZ (70mg/kg; i.p.). Traxoprodil (60mg/kg, p.o.) increased the latency to clonic and generalized seizures, and decreased the total time spent in seizures. These results support the role for the NR2B subunit in PTZ-induced seizures.[3]

Traxoprodil (5, 10, 20, and 40 mg/kg) was suspended in a 1 % aqueous solution of Tween 80 (POCH), whereas imipramine hydrochloride (15 and 30 mg/kg), fluoxetine hydrochloride (5 mg/kg), escitalopram oxalate (2 mg/kg), reboxetine mesylate (2.5 mg/kg), WAY 100,635 (0.1 mg/kg), and ritanserin (4 mg/kgh) were dissolved in physiological saline (0.9 % NaCl). The solutions/suspension were prepared immediately prior to the experiments and were administered intraperitoneally (i.p.) 60 min before testing. The doses and pretreatment schedules were selected on the basis of the literature data and the results of our previous experiments (Poleszak et al. 2005, 2007a, 2011, 2013; Szewczyk et al. 2002, 2009). Animals from the control groups received i.p. injections of the vehicle (saline). The volume of all administered solutions/suspension was 10 ml/kg.[2]

Metabolism/Metabolites>
Known human metabolites of trosoprodil include 4-[1-hydroxy-2-(4-hydroxy-4-phenylpiperidin-1-yl)propyl]benzene-1,2-diol.

[1]. Chenard BL, et al. (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidino)-1-propanol: a potent new neuroprotectant which blocks N-methyl-D-aspartate responses. J Med Chem. 1995 Aug 4;38(16):3138-45.
[2]. Poleszak E, et al. Traxoprodil, a selective antagonist of the NR2B subunit of the NMDA receptor, potentiates the antidepressant-like effects of certain antidepressant drugs in the forced swim test in mice. Metab Brain Dis. 2016 Aug;31(4):803-14.
[3]. Naspolini AP, et al. Traxoprodil decreases pentylenetetrazol-induced seizures. Epilepsy Res. 2012 Jun;100(1-2):12-9.

Trisoprodil is one of the newly discovered substances with antidepressant activity; it is a selective antagonist of the NR2B subunit of the NMDA receptor. The primary objective of this study was to evaluate the effects of trisoprodil on animal behavior using a forced swimming test (FST), and to investigate the effects of trisoprodil (10 mg/kg) on the activity of other antidepressants such as imipramine (15 mg/kg), fluoxetine (5 mg/kg), escitalopram (2 mg/kg), and reboxetine (2.5 mg/kg). Furthermore, serotonergic impairment experiments and experiments using selective 5-HT1A and 5-HT2 receptor agonists were conducted to assess the role of the serotonergic system in the antidepressant effect of trisoprodil. The concentrations of the test drugs in brain tissue were determined using high-performance liquid chromatography (HPLC). The results showed that 20 and 40 mg/kg doses of trisoprodil exhibited antidepressant activity in the forced swimming test (FST), independent of changes in animal motor activity. Co-administration of trosoprodil with subtherapeutic doses of imipramine, fluoxetine, or escitalopram significantly affected the behavior of animals in the FST, and importantly, these changes were not due to the severity of motor activity. The observed effects of trosoprodil were only partially related to the serotonergic system and were not related to the effects of 5-HT1A and 5-HT2 serotonin receptors. An attempt to assess the interaction properties of trosoprodil with the test drug indicated that an interaction exists at the pharmacokinetic stage when trosoprodil is co-administered with fluoxetine, imipramine, or escitalopram. [2]

C20H25NO3.CH4O3S

423.523

423.172

C, 59.56; H, 6.90; N, 3.31; O, 22.67; S, 7.57

188591-67-5

Traxoprodil;134234-12-1

219101

Typically exists as solid at room temperature

3.32

3

4

4

24

380

2

C[C@@H]([C@H](C1=CC=C(C=C1)O)O)N2CCC(CC2)(C3=CC=CC=C3)O.CS(=O)(=O)O

OZBWUANKVIMZIA-WRRDZZDISA-N

InChI=1S/C20H25NO3.CH4O3S/c1-15(19(23)16-7-9-18(22)10-8-16)21-13-11-20(24,12-14-21)17-5-3-2-4-6-17;1-5(2,3)4/h2-10,15,19,22-24H,11-14H2,1H3;1H3,(H,2,3,4)/t15-,19+;/m0./s1

1-[(1S,2S)-1-hydroxy-1-(4-hydroxyphenyl)propan-2-yl]-4-phenylpiperidin-4-ol;methanesulfonic acid

Traxoprodil (mesylate); I23V4CCC9V; UNII-I23V4CCC9V; CP-101606 mesylate; TRAXOPRODIL MESILATE;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)