Cariprazine is an atypical antipsychotic.1 It binds to dopamine D2L, D2S, and D3 receptors, the serotonin (5-HT) receptor subtypes 5-HT1A, 5-HT2A, and 5-HT2B, and histamine H1 and sigma-1 (σ1) receptors (Kis = 0.085-23.44 nM).2 Cariprazine is an antagonist of dopamine D2 and D3 receptors (Kbs = 0.759 and 0.316 nM, respectively, in dopamine-induced [35S]GTPγS binding assays). It is also a partial agonist at these receptors, stimulating inositol phosphate production in murine A9 cells expressing human D2L receptors (EC50 = 3.16 nM) and inhibiting forskolin-induced cAMP accumulation in CHO cells expressing human D3 receptors (EC50 = 2.63 nM). Cariprazine inhibits amphetamine-induced hyperactivity and the conditioned avoidance response in rats (ED50s = 0.12 and 0.84 mg/kg, respectively).3 It also inhibits scopolamine-induced learning deficits in a water labyrinth learning test in rats when administered at doses ranging from 0.02 to 0.08 mg/kg. Formulations containing cariprazine have been used in the treatment of schizophrenia, as well as manic, depressive, or mixed episodes associated with bipolar I disorder.
1.Mészáros, G.P., Agai-Csongor, E., and Kapás, M.Sensitive LC-MS/MS methods for the quantification of RGH-188 and its active metabolites, desmethyl- and didesmethyl-RGH-188 in human plasma and urineJ. Pharm. Biomed. Anal.48(2)388-397(2008) 2.Kiss, B., Horváth, A., Némethy, Z., et al.Cariprazine (RGH-188), a dopamine D3 receptor-preferring, D3/D2 dopamine receptor antagonist-partial agonist antipsychotic candidate: In vitro and neurochemical profileJ. Pharmacol. Exp. Ther.333(1)328-340(2010) 3.Gyertyán, I., Kiss, B., Sághy, K., et al.Cariprazine (RGH-188), a potent D3/D2 dopamine receptor partial agonist, binds to dopamine D3 receptors in vivo and shows antipsychotic-like and procognitive effects in rodentsNeurochem. Int.59(6)925-935(2011)
|
Kinase experiment: |
These assays are done in 50 mM Tris (pH 7.4), 100 mM NaCl, 7 mM MgCl2, 1 mM EDTA, and 1 mM DTT. Assay tubes (final volume 250 μL) contain 50 μM (striatum and hippocampus) or 1 μM (D2 and D3 cell membrane) GDP, the ligand to be examined, and membrane suspension (250 μg tissue/tube for the striatum and hippocampus and 20 μg protein/tube for hD2 and hD3 membranes). Samples are preincubated for 10 min at 30°C. After the addition of 50 pM [35S]GTPγS, membranes are incubated for an additional 60 min at 30°C. Nonspecific binding is determined in the presence of 10 μM GTPγS; basal binding is determined in the presence of buffer only. The assay is terminated by rapid filtration through UniFilter GF/B using a harvester, and the membranes washed four times with 1 mL of ice-cold buffer. After drying (40°C for 1 h), 40 μL of Microscint is added to the filters, and the bound radioactivity is determined by a TopCount NXT counter[2]. |
|
Cell experiment: |
Cells are seeded on a 24-well tissue culture plate in 500 μL of medium. Fifty microliters of medium containing 0.55 μCi myo-[3H]inositol is added (final concentration 1 μCi/mL) and incubated for 18-20 h. Cells are then washed three times with buffer containing 140 mM NaCl, 5 mM KCl, 2 mM CaCl2, 5 mM HEPES, 5 mM Na-HEPES, 20 mM glucose, and 10 mM LiCl (pH 7.4). Cells are then incubated for an additional 60 min (37°C) in medium with test compounds alone (agonist test) or alongside 1000 nM (±)-Quinpirole (antagonist test). Medium is then aspirated off, cells are lysed by adding 400 μL of 0.1 M HCl/2 mM CaCl2, and supernatants are frozen at ?72°C. After thawing and centrifugation at 1000g for 10 min, 200 μL of each supernatant is loaded on 250 μL of AG1-X8 (formate form) anion exchange column. Effluent is discarded, and columns are washed twice in 1.5 mL of distilled water. IPs are eluted with 2.5 mL of 1 M ammonium formate/0.1 M formic acid directly into scintillation vials, 10 mL of Optiphase HiSafe 3 is added, and the radioactivity is determined in a TriCarb 4900 scintillation counter[2]. |
|
Animal experiment: |
Mice[3] Experiments are performed on wild-type C57Bl/6J mice. In tests of cognitive functions, it is essential to employ concentrations of drugs that have no effects on emotional behavior and that do not impair locomotor activity. Whether Cariprazine (administered at a dose range of 0.005 to 0.15 mg/kg) is first tested affected the behavior of mice in the EPM, a test of anxiety-related behavior that is also critically dependent upon normal locomotor activity. Animals are exposed to an EPM apparatus designed for mice (leg height: 45 cm, arm length: 35 cm, lane width: 5 cm, wall height: 15 cm). Testing (under 100 lux lighting) is performed between 1 and 4 PM. Mice are placed in the center of the maze and their time spent in open arms and the number of closed and open arm entries during a 5 min test period is recorded. Measures of the time spent in open arms and the number of open arm entries served as a measure of anxiety-like behavior. The number of closed arm entries served as a measure of locomotor activity. Rats[4] Adult male Sprague-Dawley rats (150-300 g) are used. Cariprazine is dissolved in 0.9% saline and administered at 0.06, 0.25, 0.5, and 1.0 mg/kg via intraperitoneal (i.p.) injection 1 h before i.c.v. injection of ouabain and daily thereafter for 7 days. Open field activity is assessed immediately following the i.c.v. injection and again after 7 days (the activity is noted 10-14 h after the last i.p. injection of Cariprazine). |
|
参考文献: [1]. Seneca N, et al. Occupancy of dopamine D2 and D3 and serotonin 5-HT1A receptors by the novel antipsychotic drug candidate, cariprazine (RGH-188), in monkey brain measured using positron emission tomography. Psychopharmacology (Berl). 2011 Dec;218(3):579-8 |
|
动态评分
0.0