Vasopressin V1b Receptor (Ki = 1~3 nM)

SSR149415 showed competitive nanomolar affinity for animal and human V1b receptors and exhibited much lower affinity for rat and human V1a, V2, and oxytocin receptors. Moreover, this compound did not interact with a large number of other receptors, enzymes, or ion channels. In vitro, SSR149415 behaved as a full antagonist and potently inhibited arginine vasopressin (AVP)-induced Ca2+ increase in Chinese hamster ovary cells expressing rat or human V1b receptors. [1]

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SSR149415 is the first selective, orally active vasopressin V(1b) receptor antagonist yet described. It is a competitive antagonist with nanomolar affinity for animal and human V(1b) receptors and displays a highly selective profile with regard to a large number of receptors or enzymes. In vitro, SSR149415 potently antagonizes functional cellular events associated with V(1b) receptor activation by AVP, such as intracellular Ca(2+) increase or proliferation in various cell systems[2].

The in vivo activity of Nelivaptan (SSR-149415) has been studied in several models of elevated corticotropin secretion in conscious rats. SSR149415 inhibited exogenous AVP-induced increase in plasma corticotropin, from 3 mg/kg i.p. and 10 mg/kg p.o. upwards. Similarly, this compound antagonized AVP-potentiated corticotropin release provoked by exogenous corticoliberin at 3 mg/kg p.o. The effect lasted for more than 4 h at 10 mg/kg p.o. showing a long-lasting oral effect. SSR149415 (10 mg/kg p.o.) also blocked corticotropin secretion induced by endogenous AVP increase subsequent to body water loss. Moreover, 10 mg/kg i.p SSR149415 inhibited plasma corticotropin elevation after restraint-stress in rats by 50%. In the four-plate test, a mouse model of anxiety, SSR149415 (3 mg/kg p.o. upwards) displayed anxiolytic-like activity after acute and 7-day repeated administrations. Thus, SSR149415 is a potent, selective, and orally active V1b receptor antagonist. It represents a unique tool for exploring the functional role of V1b receptors and deserves to be clinically investigated in the field of stress and anxiety.[1]

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Pharmacological studies, performed by measuring ACTH secretion induced by various stimulants such as hormones (AVP or AVP + CRF) or physical stress (restraint or forced swimming stress and dehydration) in conscious rats or mice, confirm the antagonist profile of Nelivaptan (SSR-149415) and its efficacy in normalizing ACTH secretion in vivo. SSR149415 is active by the oral route, at doses from 3 mg/kg, it potentiates CRF effect and displays a long-lasting oral effect in the different models. At 10 mg/kg p.o. its duration of action is longer than 4 h. This molecule also decreases anxiety and exerts marked antidepressant-like activity in several predictive animal models. The anxiolytic effects of SSR149415 have been demonstrated in various Generalized Anxiety Disorders (GAD) models (four-plate, punished drinking, elevated plus-maze, light dark, mouse defense test battery, fear-potentiated startle and social interaction tests). It is as effective as the benzodiazepine diazepam in the acute stress exposure test. SSR149415 has similar efficacy to the reference antidepressant drug, fluoxetine, in acute (forced-swimming) and chronic (chronic mild stress and subordination stress) situations in rodents. SSR149415 also reduces offensive aggression in the resident-intruder model in mice and hamsters. Depending on the model, the minimal effective doses are in the range of 1-10 mg/kg i.p. or 3-10 mg/kg p.o. SSR149415 is devoid of adverse effects on motor activity, sedation, memory or cognitive functions and produces no tachyphylaxis when administered repeatedly. It is well-tolerated in animals and humans and exhibits an adequate ADME profile. Thus, SSR149415 is a new dual anxiolytic/antidepressant compound, which appears to be free of the known side effects of classical anxiolytic/antidepressant drugs. Clinical trials are in progress, they will hopefully demonstrate its therapeutical potential for treating stress-related disorders[2].

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Pretreatment with V1b Antagonist Restores Hemodynamic Function in AMI Rats [3]
Compared with the AMI group, HR was significantly decreased while MAP was significantly increased in the Nelivaptan (SSR-149415) pretreatment AMI group. Nelivaptan pretreatment ameliorated the dysfunctional LVEF (Fig. 7A, n = 3, P < 0.05) caused by AMI. In contrast to the nelivaptan treatment groups, LVEDP (Fig. 7B, n = 3, P < 0.05) was increased while +dp/dtmax /-dp/dtmax (Fig. 7C, n = 3, P < 0.01) was decreased in the AMI group. NE concentration in the serum of nelivaptan-treated rats was lower than in the AMI group (Fig. 7D, n = 3, P < 0.01). Microinjection of the VP receptor inhibitor-V1b antagonist nelivaptan into the PVN restored hemodynamic function of and NE level in AMI rats.

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Typical responses to unilateral microinjection of 100 ng VP or after the V1b antagonist, Nelivaptan (SSR-149415) , into the PVN of conscious rats are depicted in Fig. 2A. Raw nerve recordings (10 s in duration) at baseline after saline or V1b antagonism and at 10 min after VP injection are shown in Fig. 2B. A recording of residual nerve activity after ganglionic blockade with trimethaphan camsylate is also included (Fig. 2Be). Microinjection with Nelivaptan (SSR-149415) , the V1b receptor antagonist, into the PVN did not alter baseline MAP or heart rate such that the values were similar to those after injection with saline vehicle (Table 1). [4]
Mean haemodynamic and RSNA data for all animals are shown in Fig. 3. After VP administration, elevations in MAP, heart rate and RSNA were observed, with peak responses at 10 min. All parameters achieved significance compared with baseline, with MAP achieving significance from the third minute forward, heart rate from the second minute onward and RSNA from the fifth minute until the end of the experiment. Pretreatment with nelivaptan inhibited the pressor, tachycardic and RSNA responses observed with VP alone such that no significant changes from baseline occurred in any of the parameters. Compared with the responses to VP alone, MAP, heart rate and RSNA were significantly lower when VP was administered after nelivaptan in the same animals. Figure 4 shows the aggregate changes in MAP, heart rate and RSNA at both the 5 and the 10 min marks for rats treated with VP alone and the same rats treated with VP after V1b antagonist. In two instances, microinjections occurred outside (one dorsal and one lateral) to the PVN. In these two cases, the average changes in heart rate (6.2 beats min−1), MAP (1.2 mmHg) and RSNA (−1.1% baseline) were negligible and did not change with V1b antagonism [4].

Forty-eight rats that survived AMI surgery were randomly placed into Sham, AMI, AMI + DPI (diphenyleneiodonium, a NOX inhibitor), and AMI + Nelivaptan (SSR-149415) groups. The rats received PVN microinjection of DPI (100 μmol/0.1 μL) or Nelivaptan (SSR-149415) (40 ng/0.1 μL) 15 min before 4 h AMI surgery. The dose of nelivaptan was chosen based on previous reports. The same volume of corresponding solvent was used as vehicle control.[3]

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The dose of VP was chosen based on previously reported studies of VP injected either intracerebroventricularly (i.c.v.; Berecek et al. 1984a; Unger et al. 1986; Janiak et al. 1989) or into other central loci (Matsuguchi et al. 1982; Berecek et al. 1984b) Prior to performing any of the protocols, we sought to identify the dose of V1b antagonist, Nelivaptan (SSR-149415), that would fully block the increase in MAP evoked by a maximally stimulating dose of VP (100 ng) administered into the PVN of rats instrumented only with vascular catheters and a PVN cannula. The increases in MAP in response to VP microinjected 10 min after saline vehicle alone or 0.1, 0.5, 10 or 100 ng Nelivaptan (SSR-149415) were as follows: 17.4 ± 3.8, 10.8 ± 1.9, 7.45 ± 1.9, 4.2 ± 0.7 and 1.3 ± 2.8 mmHg, respectively (n = 4 for each dose). Microinjection of 100 ng VP without any prior injection resulted in an increase in MAP of 17.8 ± 3.8 mmHg. We, therefore, chose 100 ng nelivaptan for all subsequent protocols. [3]
Protocol 1[3]
One day after placement of the nerve electrodes, the rat was placed in the study chamber and the catheters and electrodes were connected for the measurement of MAP, heart rate and RSNA. The obturator was replaced with a 33 gauge infusion cannula, which extended 1 mm beyond the tip of the guide cannula and connected to PE20 tubing connected to a Hamilton syringe for microinjection into the PVN. After 30–60 min of stabilization, 100 ng VP in 250 nl isotonic saline or saline vehicle alone was microinjected unilaterally into the PVN. After all parameters had returned to baseline (∼90 min), 100 ng of the V1b receptor antagonist (Nelivaptan (SSR-149415) was injected, followed by 100 ng VP 10 min later. The MAP, heart rate and RSNA were recorded for an additional 10 min. One group of rats was used for this experiment.[4]

[1]. Characterization of (2S,4R)-1-[5-Chloro-1-[(2,4-dimethoxyphenyl)sulfonyl]-3-(2-methoxy-phenyl)-2-oxo-2,3-dihydro-1H-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidine carboxamide (SSR149415), a Selective and Orally Active Vasopressin V1b Receptor Antagonist. Journal of Pharmacology and Experimental Therapeutics March 2002, 300 (3) 1122-1130.

[2]. An overview of SSR149415, a selective nonpeptide vasopressin V(1b) receptor antagonist for the treatment of stress-related disorders. CNS Drug Rev. 2005 Spring;11(1):53-68.

[3]. Paraventricular Nucleus P2X7 Receptors Aggravate Acute Myocardial Infarction Injury via ROS-Induced Vasopressin-V1b Activation in Rats. Neurosci Bull. 2021 May;37(5):641-656.

[4]. Haemodynamic and renal sympathetic responses to V1b vasopressin receptor activation within the paraventricular nucleus. Exp Physiol . 2015 Apr 20;100(5):553-65.

Nelivaptan has been used in trials for the treatment of anxiety disorders, depression, and major depressive disorder. The discovery of SSR149415, the first selectively orally administered active V1b receptor antagonist, provided an opportunity to broadly characterize the AVPvV1b receptor system in various in vitro and in vivo models. Results showed that AVP controls mood processes or stress-related disorders by activating V1b receptors, suggesting that V1b receptor blockade may represent an innovative therapy for certain types of anxiety and depression. Hypothalamic-pituitary-adrenal (HPA) axis overactivity is common in clinical depression and anxiety disorders, and studies have shown that antidepressants can restore HPA axis activity and cortisol levels to normal in patients with depression. The AVPvV1b receptor system appears to control stress responses through both peripheral and central effects via pituitary V1b receptors. Arginine vasopressin (AVP), produced by hypothalamic neurons, can activate the release of adrenocorticotropic hormone (ACTH), thereby promoting cortisol secretion. Furthermore, AVP released in multiple central nervous system regions can bind to central V1b receptors in limbic system structures such as the lateral septum, hippocampus, or amygdala, thereby generating stress-adaptive responses. Our results using SSR149415 in various animal models support this dual hypothesis. First, SSR149415 reduces the increase in ACTH and cortisol secretion induced by various stimuli (such as hormones, AVP, and AVP+CRF) and physical stress (such as restraint or forced swimming tests and dehydration), without affecting the normal hypothalamic-pituitary-adrenal (HPA) axis response to stress observed in rat CRF stimulation tests. Second, antidepressant-like effects (albeit at a lower intensity) were observed in both normal rats and pituitary-resectomized rats in the forced swimming test, suggesting that the mechanism of action of this compound involves more than just pituitary-adrenal axis blockade. Furthermore, SSR149415, administered intravenously (ICV) to the lateral septum or amygdala of rats, induced significant dose-dependent antidepressant-like effects, indicating the involvement of central V1b receptors in these effects. SSR149415 treatment was also associated with neurochemical changes in specific brain regions, such as controlling norepinephrine release in the prefrontal cortex under stress conditions or restoring hippocampal neurogenesis damaged by chronic stress. Recently, a neurochemical study combining microdialysis and behavioral research provided new insights into the central mechanism of action of SSR149415, supporting its anxiolytic and antidepressant-like properties. Peripheral injection of SSR149415 (3 to 30 μg/kg, intraperitoneal) significantly and specifically increased extracellular norepinephrine and γ-butyrate (GABA) concentrations in the rat prefrontal cortex without affecting the levels of other neurotransmitters such as serotonin, dopamine, and glutamate. The authors report that the increase in extracellular norepinephrine was similar to that observed with reference antidepressants such as venlafaxine or desipramine. Furthermore, the anxiolytic-like activity of SS149415 may be mediated by elevated prefrontal GABA levels. Therefore, the selective inhibition of V1b receptors by SSR149415 is associated with central neurochemical changes, which could explain the molecule's dual anxiolytic/antidepressant properties. Regulation of corticosteroid receptor expression may also be an important target in the mechanism of action of SSR149415. Disruptions in corticosteroid feedback are associated with the pathological mechanisms of stress and depression, explaining elevated levels of corticotropin-releasing factor (CRF) and arginine vasopressin (AVP), as well as enhanced activity of the hypothalamus-pituitary-adrenal (HPA) axis. Studies have shown that AVP and CRF regulate corticosteroid receptor levels in the hippocampus and anterior pituitary. During intermittent restraint stress, the expression of nonselective V1b receptor antagonists increased in both tissues. Whether V1b receptor blockers can provide an effective alternative to existing drug treatments for depression and anxiety remains a key question. Clinical trials will be the next step in evaluating SSR149415. As described in this chapter, SSR149415 reduces anxiety levels in rodents and is as effective as diazepam in acute or traumatic stress exposure. Its mechanism of action is similar to that of fluoxetine in all tested acute and chronic depression models. Indeed, depression and anxiety are heterogeneous diseases with multiple etiologies, and this heterogeneity explains the difficulty in treating these diseases with specific drugs. This also explains why there are a large number of treatment-resistant patients. SSR149415 offers a novel approach to treating anxiety and/or depression through a completely new mechanism of action. Currently, it is impossible to speculate on the activity spectrum and efficacy of this molecule in treating patients with anxiety and depression, alone or in combination with standard treatments. While there are expectations that future antidepressants will have a faster onset of action, animal studies using SSR149415 in appropriate models (such as CMS) do not support this expectation. Due to its high selectivity, targeting only the V1b receptor, SSR149415 may have fewer side effects compared to currently used anxiolytics/antidepressants. In vivo pharmacological studies using acute, repeated, and high-dose administration have confirmed that SSR149415 is well-tolerated, without rapid tolerance or mood-related central nervous system side effects. The drug also has no effect on motor activity or sleep patterns. Although SSR149415 did not affect spatial memory in the Morris water maze test in mice or rats, it is premature to conclude that the drug has no effect on learning and memory. Further studies in other memory models are needed to gain a clearer understanding of the potential or non-existent effects of SSR149415 on cognitive function. Furthermore, whether long-term treatment with SSR149415 affects memory processes remains to be determined. In summary, SSR149415 is the first reported selective V1b receptor antagonist. It provides a unique tool for further exploration of the unknown roles of pituitary and extrapituitary V1b receptors. With the help of this molecule, the important role of the AVP1V1b receptor system in controlling mood disorders has been revealed. Clinical evaluation of SSR149415 is eagerly anticipated to confirm the therapeutic potential of V1b receptor blockade in treating stress-related diseases. In addition, other functions of AVP V1b-R and other therapeutic indications for antagonists should be further explored using selective V1b ligands. Recent data in V1b-R knockout mice suggest that V1b-R plays a role in schizophrenia. [2]

C30H32CLN3O8S

630.1

629.16

C, 57.19; H, 5.12; Cl, 5.63; N, 6.67; O, 20.31; S, 5.09

439687-69-1

9895468

White to off-white solid powder

3.952

1

9

8

43

1140

3

CN(C)C(=O)[C@@H]1C[C@H](CN1[C@]2(C3=C(C=CC(=C3)Cl)N(C2=O)S(=O)(=O)C4=C(C=C(C=C4)OC)OC)C5=CC=CC=C5OC)O

NJXZWIIMWNEOGJ-WEWKHQNJSA-N

InChI=1S/C30H32ClN3O8S/c1-32(2)28(36)24-15-19(35)17-33(24)30(21-8-6-7-9-25(21)41-4)22-14-18(31)10-12-23(22)34(29(30)37)43(38,39)27-13-11-20(40-3)16-26(27)42-5/h6-14,16,19,24,35H,15,17H2,1-5H3/t19-,24+,30+/m1/s1

(2S,4R)-1-[(3R)-5-Chloro-1-(2,4-dimethoxyphenyl)sulfonyl-3-(2-methoxyphenyl)-2-oxoindol-3-yl]-4-hydroxy-N,N-dimethylpyrrolidine-2-carboxamide

Nelivaptan; SR-149415; Nelivaptan; 439687-69-1; SSR 149,415; SSR149,415; Nelivaptan [INN]; SR-149,415; SSR-149,415; (2S,4R)-1-[(3R)-5-chloro-1-(2,4-dimethoxyphenyl)sulfonyl-3-(2-methoxyphenyl)-2-oxoindol-3-yl]-4-hydroxy-N,N-dimethylpyrrolidine-2-carboxamide; SR 149415; SSR149415

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

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.)