5-HT2C Receptor

Ro60-0175 , or (2S)-1-(6-chloro-5-fluoroindol-1-yl)-propan-2-amine is a 1-(6-chloro-5-fluoroindol-1-yl)-propan-2-amine that has S configuration. A selective agonist for both the 5-hydroxytryptamine 2B (5-HT2B) and 5-hydroxytryptamine 2C (5-HT2C)serotonin receptor subtypes, commonly used as fumarate salt. It has a role as a 5-hydroxytryptamine 2B receptor agonist and a 5-hydroxytryptamine 2C receptor agonist.

Ro60-0175 (1 mg/kg; subcutaneous injection) retained the regular responses observed in drug-treated control animals, but drug-treated animals reached their turning point earlier [1]. Ro60-0175 (0.3, Ro60-0175 (0.5 mg/kg SB242084; 1 mg/kg Ro60-0175; subcutaneous injection) versus vehicle 1 and 3 mg/kg; subcutaneous injection) in the recovery group significantly reduced the response to active levers in the recovery group response[1]. In contrast, the response was reduced, and weight loss with SB242084 prevented this effect. There were no significant main effects or interactions for responses to the inactive lever [1].

Animal/Disease Models: Adult male SD (SD (Sprague-Dawley)) rats (280-320 g)[1]
Doses: 1 mg/kg
Route of Administration: subcutaneous injection
Experimental Results: Control animals in the drug treatment group retained the regularity of responses, but drug treatment of animals reached the breakpoint earlier.

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Animal/Disease Models: Adult male SD (SD (Sprague-Dawley)) rat (280-320 g) [1]
Doses: 0.5 mg/kg (SB242084), 1 mg/kg (Ro60-0175)
Route of Administration: sc (Ro60-0175), ip (SB242084)
Experimental Results: SB242084 diminished the response to cocaine and the effects were reversed.

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Animal/Disease Models: Adult male SD (SD (Sprague-Dawley)) rat (280-320 g) [1]
Doses: 0.3, 1 and 3 mg/kg (Ro60-0175), 1 mg/kg (yohimbine)
Route of Administration: subcutaneous injection (Ro60-0175), intraperitoneal (ip) injection (yohimbine)
Experimental Results: Yohimbine treatment alone increased the response relative to vehicle injection and this response was dose-dependently attenuated by Ro60-0175.

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Animal/Disease Models: Adult male SD (SD (Sprague-Dawley)) rat (280-320 g) [1]
Doses: 0.5 mg/kg (SB242084), 1 mg/kg (Ro60-0175), 1 mg/kg (yohimbine) Ad

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\nRo60-0175 was dissolved in 0.9% saline and injected s.c.[1]
\n\nExperiment 1a: Effect of daily treatment with Ro60-0175 on cocaine self-administration[1]
\nBefore surgery rats were trained to lever press for food pellets. Rats were food restricted (approximately 18 g/day) placed in the operant chambers and trained to press the left lever for food (45 mg Noyes pellets) according to a FR 1 schedule. Rats were allowed a maximum of 100 pellets during daily 30 min sessions. Any rats failing to obtain 100 pellets by the 3rd day of training were placed in the operant boxes overnight and allowed 300 food pellets delivered according to the FR1 schedule. A stainless-steel dish filled with water was also placed inside the operant chamber during this session. Thereafter, rats were placed in the chamber only during the 30 min daytime session. Once rats had received 100 pellets on each of three consecutive days they were considered lever-trained, and were subsequently maintained on approximately 20 g of lab chow per day. One week after catheters were implanted rats were allowed to respond for infusions (0.1 ml during 5.5 s) of cocaine (0.25 mg/infusion delivered in 0.1 ml) on a FR1 schedule. Each infusion was accompanied by a stimulus light that remained on for a 20 s time-out period after the infusion. Once responding was stable, a progressive ratio schedule was implemented in which the number of responses required to obtain an infusion increased for successive infusions. The progression was derived from the equation: response ratio=[5e(0.2 × infusion no.)−5], and yielded response ratios of 1, 2, 4, 6, 9, 12, 15, 20, 25, 32, 40, 50, 62, 77, 95, 118, etc (Richardson and Roberts, 1996). Sessions lasted until a period of 1 h without an infusion had elapsed, or were a maximum of 5 h in length. The number of infusions earned before this breaking point was recorded. The infusion dose was held constant at 0.25 mg/infusion throughout. Testing began when break points did not vary by more than 15% on three consecutive days. At this point, rats were assigned to two groups matched for daily number of cocaine infusions. One group received injections of 1 mg/kg Ro60-0175 (s.c.) 15 min before being placed in the self-administration chambers; the other groups received injections of saline. Testing was conducted on eight consecutive days. Eight rats in the saline group and eight rats in the Ro60-0175 group completed the experiment.\n

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\nExperiment 1b: Interaction between SB242084 and Ro60-0175 on cocaine self-administration[1]
\nA further nine rats were trained to respond for cocaine (0.25 mg/infusion) as described above. Once breaking points were stable drug testing began. Each rat was tested on four occasions spaced a minimum of 72 h apart. On these test days rats were first injected with 0.5 mg/kg SB242084 or its vehicle (i.p.), 30 min later they received an injection of 1 mg/kg Ro60-0175 (s.c.) or saline. Fifteen minutes later rats were placed in the drug self-administration chambers. The order of treatments was determined from Latin Squares with approximately equal numbers of animals being tested at each treatment level. On non-drug test days the usual self-administration session was in effect.\n

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\nExperiment 2a: Effects of Ro60-0175 on reinstatement induced by yohimbine[1]
\nThe experimental design for this experiment, and all subsequent experiments, involved three phases: cocaine self-administration, extinction of bar-pressing, and tests for reinstatement. Eleven rats were trained to respond for cocaine (0.25 mg/infusion) delivered according to a FR1 schedule, as outlined above. Again cocaine infusions were accompanied by illumination of the stimulus light for 20 s. Self-administration sessions were 2 h in duration; 15 sessions were run on consecutive days. At the end of this period, extinction conditions were in effect. Here drug syringes were removed from the pumps so that responses on the previously active lever activated the stimulus light but no longer delivered cocaine infusions. Extinction sessions were run for 8 days at which point responding on the active lever had reached a low, stable level of <15 responses in 2 h. At this point rats were tested on five occasions separated by a minimum period of 72 h. On these occasions, rats were first given a 2 h extinction session with no drug treatments. At the end of this period, the animals received an injection of 1 mg/kg yohimbine or saline (i.p.) and returned to the home cage. Thirty minutes later rats received a second injection of Ro60-0175 or saline (s.c.); 15 min later rats were returned to the self-administration chamber for another 2 h extinction session. The five-treatment combinations that were tested were: vehicle saline, and 1 mg/kg yohimbine in combination with saline, 0.3, 1, and 3 mg/kg Ro60-0175. The order of treatments was determined from Latin Squares. On the days between tests, rats were run as normal with a 2 h extinction session. The dose of yohimbine was chosen based on a consideration of published work (Shepard et al, 2004) and the results of a pilot study.\n

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\nExperiment 2b: Interaction between SB242084 and Ro60-0175 on reinstatement induced by yohimbine[1]
\nNine rats went through the same cocaine self-administration and extinction procedures as described for Experiment 2a. In this experiment, extinction was conducted for 12 days before reinstatement testing began. Four testing days were conducted. On each test all rats received injections of 1 mg/kg yohimbine at the end of a 2 h extinction phase and were returned to the home cage. Fifteen minutes later rats were treated with 0.5 mg/kg SB242084 or its vehicle, followed 30 min later by 1 mg/kg Ro60-0175 or saline. After a further 15 min, rats were returned to the self-administration chamber for a 2 h extinction session. All rats were tested under all four-treatment combinations spaced at least 72 h apart; the order of treatments was determined from Latin Squares.\n

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\nExperiment 3a: Effects of Ro60-0175 on reinstatement induced by contextual cues[1]
\nThis experiment examined the effects of Ro60-0175 on the reinstatement of cocaine-seeking induced by contextual cues. The experiment required the use of two different contexts in which the three phases of the experiment (self-administration, extinction, and reinstatement) were conducted. The experiment began with the acquisition of cocaine self-administration (15 days), followed by extinction training (22 days) and testing for reinstatement of cocaine seeking (10 days). Rats were assigned to a reinstatement group (n=8) or a control group (n=8). For rats in the reinstatement group cocaine self-administration occurred in one context (A), extinction occurred in the alternative context (B), and reinstatement testing was conducted in context A. For the control group self-administration occurred in context A, and extinction and reinstatement both occurred in context B. In one context, operant chambers had a textured Plexiglas floor insert; the chamber houselight, and the ventilating fans within the sound-attenuating chamber were both turned on. Sessions in this context began 2 h following light offset in the colony room. In the alternate context, operant chambers were located in a different area of the lab. These chambers had the standard stainless-steel rod floors; the houselight and ventilating fans were both turned off. Sessions in the alternate context began 5 h following light offset in the colony room.
\n\nFor the cocaine self-administration phase rats were trained to respond for cocaine infusions (0.25 mg in 0.1 ml over 5.5 s) according to a FR1 schedule as described for Experiments 1 and 2. Cocaine infusions were accompanied by a 20 s illumination of the houselight during which time further lever presses were recorded but not reinforced. Fifteen 2 h sessions of self-administration were conducted. During the extinction phase syringes were removed from the pumps, responses on the formerly active lever activated the stimulus light but no longer delivered cocaine infusions. During the reinstatement phase each rat was tested four times beginning 15 min after treatment with 0.3, 1, and 3 mg/kg Ro60-0175 and saline. The order of treatment was determined from Latin Squares. Tests were spaced at least 72 h apart, and rats were run under their appropriate extinction conditions on intervening days.\n

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\nExperiment 3b: Interaction between SB242084 and Ro60-0175 on reinstatement induced by contextual cues[1]
\nThis experiment used eight rats in the reinstatement group, and eight rats in the control group. The behavioral procedures for self-administration, extinction, and reinstatement were identical to those for Experiment 3a. On reinstatement days rats were tested with every combination of 0.5 mg/kg SB242084 or its vehicle and 1 mg/kg Ro60-0175 or saline. The injections were given 30 min apart, and testing began 15 min after the second injection. The order of treatment was determined from Latin Squares. Tests were spaced at least 72 h apart, and rats were run under their appropriate extinction conditions on intervening days.

[1]. Fletcher PJ, et al. The 5-HT2C receptor agonist Ro60-0175 reduces cocaine self-administration and reinstatement induced by the stressor yohimbine, and contextual cues. Neuropsychopharmacology. 2008;33(6):1402-1412.

(2S)-1-(6-chloro-5-fluoroindol-1-yl)-propyl-2-amine is an S-configuration 1-(6-chloro-5-fluoroindol-1-yl)-propyl-2-amine. It is a selective agonist of both serotonin receptor subtypes, 5-HT2B and 5-HT2C, and is typically used in fumarate form. It is an agonist of both 5-HT2B and 5-HT2C receptors. Previously, we demonstrated that the 5-HT2C receptor agonist Ro60-0175 reduces cocaine self-dosing and inhibits cocaine relapse after drug craving subsides. This experiment further extends these findings, aiming to determine whether the effect of Ro60-0175 on self-dosing can be maintained by repeated dosing, and whether Ro60-0175 alters relapse behavior induced by the pharmacological stressor yohimbine or the self-dosing context. In Experiment 1, Ro60-0175 (1 mg/kg, subcutaneous) reduced cocaine (0.25 mg/dose) self-administration behavior maintained by a progressive ratio reinforcement program. This reduction lasted for 8 days. In Experiment 2, rats were subjected to FR1 reinforcement program with 2 hours of cocaine self-administration daily for 15 days. After regression, yohimbine (1 mg/kg, intraperitoneal) restored the response, while Ro60-0175 (0.3–3 mg/kg, subcutaneous) dose-dependently reduced this effect. In Experiment 3, rats were trained to respond to cocaine using an FR1 reinforcement program in a specific environment (A); this response was subsequently regressed in another environment (B). Recovery tests were conducted in either environment A or B. Recovery of the response only occurred when rats were tested in the initial self-administration environment (A). Ro60-0175 dose-dependently reduced this recovery. All effects of Ro60-0175 can be blocked by the 5-HT2C receptor antagonist SB242084. Therefore, Ro60-0175 acts via the 5-HT2C receptor, reducing cocaine self-administration and drug-seeking behavior triggered by stressors and drug-related cues. The effects of Ro60-0175 did not show tolerability during the 8-day test period. These results suggest that selective 5-HT2C receptor agonists may be an effective pharmacological strategy for treating drug abuse. [1]

C11H12CLFN2

226.679

226.067

C, 58.29; H, 5.34; Cl, 15.64; F, 8.38; N, 12.36

169675-08-5

Ro60-0175 fumarate;169675-09-6; 169675-08-5

3045227

White to light yellow solid powder

1.3±0.1 g/cm3

353.2±32.0 °C at 760 mmHg

167.4±25.1 °C

0.0±0.8 mmHg at 25°C

1.595

3

1

2

2

15

227

1

ClC1C(=CC2C=CN(C=2C=1)C[C@H](C)N)F

XJJZQXUGLLXTHO-ZETCQYMHSA-N

InChI=1S/C11H12ClFN2/c1-7(14)6-15-3-2-8-4-10(13)9(12)5-11(8)15/h2-5,7H,6,14H2,1H3/t7-/m0/s1

(S)-1-(6-chloro-5-fluoro-1H-indol-1-yl)propan-2-amine

Ro60-0175; Ro-60-0175; Ro 60-0175; Ro600175; Ro-600175; Ro 600175; (2S)-1-(6-chloro-5-fluoroindol-1-yl)propan-2-amine; CHEMBL76781; (S)-1-(6-chloro-5-fluoro-1H-indol-1-yl)propan-2-amine;

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)

DMSO : ~125 mg/mL (~551.44 mM)

Solubility in Formulation 1: ≥ 2.08 mg/mL (9.18 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (9.18 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

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Solubility in Formulation 3: ≥ 2.08 mg/mL (9.18 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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