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Australian Journal of Chemistry Australian Journal of Chemistry Society
An international journal for chemical science
REVIEW

Quipazine: Classical hallucinogen? Novel psychedelic?

Richard A. Glennon https://orcid.org/0000-0002-3600-9045 A * and Maƚgorzata Dukat A
+ Author Affiliations
- Author Affiliations

A Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Box 23298, Richmond, VA 23298, USA.




Richard A. Glennon: Following BSc (Pharmacy) and MSc (Medicinal Chemistry) degrees from Northeastern University, he subsequently received his PhD (Medicinal Chemistry) from the State University of New York (SUNY; Buffalo) and obtained an NIH postdoctoral fellowship in psychopharmacology (School of Medicine; SUNY). He joined the Department of Medicinal Chemistry at Virginia Commonwealth University (VCU) as Assistant Professor and eventually achieved the rank of Professor. During his tenure, he served as Department Chair, was Alfred and Frances Burger Distinguished Professor of Medicinal Chemistry and received several honors including induction into the ACS Medicinal Chemistry Hall of Fame. He currently holds an Emeritus Professor position at VCU.



Maƚgorzata Dukat: Subsequent to an engineering (MSc Engineering) degree from T. Kosciuszko Technical University, she obtained her PhD from the prestigious Nicolaus Copernicus Academy of Medicine, Jagiellonian University, Krakow, Poland, and conducted her research at the Institute of Pharmacology, Polish Academy of Science, Krakow. After postdoctoral training in the Department of Medicinal Chemistry, School of Pharmacy and the Department of Pharmacology and Toxicology, School of Medicine at Virginia Commonwealth University (VCU), she was appointed Assistant Professor in the Department of Medicinal Chemistry at VCU where she is currently Associate Professor. She has received several distinctions including the Kosciuszko Eminent Scientist award.

* Correspondence to: glennon@vcu.edu

Handling Editor: Craig Hutton

Australian Journal of Chemistry 76(5) 288-298 https://doi.org/10.1071/CH22256
Submitted: 4 December 2022  Accepted: 28 February 2023   Published: 2 May 2023

© 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing.

Abstract

Quipazine, first identified in the 1960s, has been the topic of >1000 published papers. On the basis of available 5-HT2 serotonin receptor radioligand binding data and various preclinical studies, it might be thought that quipazine bears the hallmarks of a classical hallucinogen or psychedelic agent – agents currently being examined for their potential use in treating certain neuropsychiatric disorders. Nevertheless, by definition, such agents require the availability of human data, which, in the case of quipazine, are lacking. Because quipazine is also a 5-HT3 receptor agonist, future human studies with this agent might prove problematic because 5-HT3 agonists are known to produce emesis. Nevertheless, continued investigation of novel quipazine analogs with modified pharmacological profiles might prove worthwhile.

Keywords: 5-HT2, 5-HT3, antidepressants, arylpiperazines, drug discrimination, head-twitch assay, indolealkylamines, l.s.d., neuropsychiatric agents, phenylalkylamines, quipazine, serotonin receptors.


References

[1]  FDA alerts health care professionals of potential risks associated with compounded ketamine nasal spray. 16 February 2022. US Food and Drug Administration, Silver Spring, MD, USA. Available at https://www.fda.gov/drugs/human-drug-compounding/fda-alerts-health-care-professionals-potential-risks-associated-compounded-ketamine-nasal-spray [accessed 30 November 2022].

[2]  Glennon RA, Iversen LE. Antidepressants. In: Glennon RA, volume editor. Burger’s Medicinal Chemistry. Wiley; 2021. pp. 331–386.

[3]  AC Kwan, DE Olson, KH Preller, BL Roth, The neural basis of psychedelic action. Nat Neurosci 2022, 25, 1407.
         | The neural basis of psychedelic action.Crossref | GoogleScholarGoogle Scholar |

[4]  E Hong, EG Pardo, On the pharmacology of 2-(1-piperazinyl)quinoline. J Pharmacol Exp Ther 1966, 153, 259.

[5]  E Hong, LF Sancilio, R Vargas, EG Pardo, Similarities between the pharmacological actions of quipazine and serotonin. Eur J Pharmacol 1969, 6, 274.
         | Similarities between the pharmacological actions of quipazine and serotonin.Crossref | GoogleScholarGoogle Scholar |

[6]  R Rodríguez, EG Pardo, Quipazine, a new type of antidepressant agent. Psychopharmacologia 1971, 21, 89.
         | Quipazine, a new type of antidepressant agent.Crossref | GoogleScholarGoogle Scholar |

[7]  R Samanin, S Bernasconi, A Quattrone, Antinociceptive action of quipazine: relation to central serotonergic receptor stimulation. Psychopharmacologia 1976, 46, 219.
         | Antinociceptive action of quipazine: relation to central serotonergic receptor stimulation.Crossref | GoogleScholarGoogle Scholar |

[8]  R Samanin, C Bendotti, F Miranda, S Garattini, Decrease of food intake by quipazine in the rat: relation to serotoninergic receptor stimulation. J Pharm Pharmacol 1977, 29, 53.
         | Decrease of food intake by quipazine in the rat: relation to serotoninergic receptor stimulation.Crossref | GoogleScholarGoogle Scholar |

[9]  Szara S. Are hallucinogens psychoheuristic? In: Lin GC, Glennon RA, editors. Hallucinogens: an update. U.S. Government Printing Office; 1994. pp. 33–51.

[10]  Schultes RE, Hofmann A. Hallucinogenic or psychotomimetic agents: What are they? In: Kugelmass IN editor. The botany and chemistry of hallucinogens. Charles C. Thomas; 1973. pp. 3–12.

[11]  Hollister LE. Types of psychotomimetic drugs. In: Kugelmass IN editor. Chemical psychoses: LSD and related drugs. Charles C. Thomas; 1968. pp. 17–31.

[12]  What are hallucinogens? Hallucinogenic DrugFacts. National Institute on Drug Abuse, Baltimore, MD, USA. Available at https://nida.nih.gov/publications/drugfacts/hallucinogens [accessed 25 November 2022].

[13]  Jacob III P, Shulgin AT. Structure-activity relationships of classic hallucinogens. In: Lin GC, Glennon RA, editors. Hallucinogens: an update. U.S. Government Printing Office; 1994. pp. 74–91.

[14]  Glennon RA. Classical hallucinogens. In: Schuster CR, Kuhar MJ, editors. Handbook of experimental pharmacology: pharmacological aspects of drug dependence. Springer Verlag; 1996. pp. 343–371.

[15]  Woolley DW The biochemical bases of psychoses or the serotonin hypothesis about mental diseases. John Wiley and Sons; 1962.

[16]  RA Glennon, Do classical hallucinogens act as 5-HT2 agonists? Neuropsychopharmacology 1990, 3, 509.

[17]  RA Glennon, The 2014 Philip S. Portoghese Medicinal Chemistry Lectureship: The “Phenylalkylaminome” with a focus on selected drugs of abuse. J Med Chem 2017, 60, 2605.
         | The 2014 Philip S. Portoghese Medicinal Chemistry Lectureship: The “Phenylalkylaminome” with a focus on selected drugs of abuse.Crossref | GoogleScholarGoogle Scholar |

[18]  Glennon RA. The pharmacology of serotonergic hallucinogens and designer drugs. In: Graham AW, Schultz TK, Mayo-Smith M, Ries RK, Wilford BB, editors. Principles of addiction medicine. American Society of Addiction Medicine; 2003. pp. 275–281.

[19]  Stafford P. Overview. In: Radulovic S and Orfali S editors. Psychedelics Encyclopedia. And/Or Press; 1977. pp. 1–23.

[20]  Siegel R. The natural history of hallucinogens, In: Jacobs BL, editor. Hallucinogens: neurochemical, behavioral, and clinical perspectives. Raven; 1984. pp. 1–18.

[21]  E Pottie, CP Stove, In vitro assays for the functional characterization of (psychedelic) substances at the serotonin receptor 5-HT2A R. J Neurochem 2022, 162, 39.
         | In vitro assays for the functional characterization of (psychedelic) substances at the serotonin receptor 5-HT2A R.Crossref | GoogleScholarGoogle Scholar |

[22]  SJ Peroutka, SH Snyder, Multiple serotonin receptors: differential binding of [3H]5-hydroxytryptamine, [3H]lysergic acid diethylamide and [3H]spiroperidol. Mol Pharmacol 1979, 16, 687.

[23]  NM Barnes, GP Ahern, C Becamel, J Bockaert, M Camilleri, S Chaumont-Dubel, S Claeysen, KA Cunningham, KC Fone, M Gershon, G Di Giovanni, NM Goodfellow, AL Halberstadt, RM Hartley, G Hassaine, K Herrick-Davis, R Hovius, E Lacivita, EK Lambe, M Leopoldo, FO Levy, SCR Lummis, P Marin, L Maroteaux, AC McCreary, DL Nelson, JF Neumaier, A Newman-Tancredi, H Nury, A Roberts, BL Roth, A Roumier, GJ Sanger, M Teitler, T Sharp, CM Villalón, H Vogel, SW Watts, D Hoyer, International Union of Basic and Clinical Pharmacology. CX. Classification of receptors for 5-hydroxytryptamine; pharmacology and function. Pharmacol Rev 2021, 73, 310.
         | International Union of Basic and Clinical Pharmacology. CX. Classification of receptors for 5-hydroxytryptamine; pharmacology and function.Crossref | GoogleScholarGoogle Scholar |

[24]  Glennon RA, Rosecrans JA, Young R The use of the drug discrimination paradigm for studying hallucinogenic agents. In: Colpaert FC, Slangen JL, editors. Drug discrimination: applications in CNS pharmacology. Elsevier Biomedical Press; 1982; pp. 69–96.

[25]  F Zamberlan, C Sanz, R Martínez Vivot, C Pallavicini, F Erowid, E Erowid, E Tagliazucchi, The varieties of the psychedelic experience: a preliminary study of the association between the reported subjective effects and the binding affinity profiles of substituted phenethylamines and tryptamines. Front Integr Neurosci 2018, 12, 54.
         | The varieties of the psychedelic experience: a preliminary study of the association between the reported subjective effects and the binding affinity profiles of substituted phenethylamines and tryptamines.Crossref | GoogleScholarGoogle Scholar |

[26]  DL Nelson, VL Lucaites, DB Wainscott, RA Glennon, Comparisons of hallucinogenic phenylisopropylamine binding affinities at cloned human 5-HT2A, 5-HT2B and 5-HT2C receptors. Naunyn Schmiedebergs Arch Pharmacol 1999, 359, 1.
         | Comparisons of hallucinogenic phenylisopropylamine binding affinities at cloned human 5-HT2A, 5-HT2B and 5-HT2C receptors.Crossref | GoogleScholarGoogle Scholar |

[27]  Glennon RA. Animal models for assessing hallucinogenic agents. In: Boulton AA, Baker GB, Wu PH, editors. Animal models of drug addiction. Humana Press; 1992. pp. 345–381.

[28]  Halberstadt AL, Geyer MA. Hallucinogens. In: Koob GF, Moal ML, Thompson RF, editors. Encyclopedia of behavioral neuroscience. Academic Press; 2010. pp. 12–20.

[29]  Stollerman IP. The discrimination of drug mixtures. In: Glennon RA, Young R, editors. Drug discrimination: applications to medicinal chemistry and drug studies. Wiley; 2011. pp. 323–359.

[30]  NA Darmani, BR Martin, U Pandey, RA Glennon, Pharmacological characterization of ear-scratch response in mice as a behavioral model for selective 5-HT2-receptor agonists and evidence for 5-HT1B- and 5-HT2-receptor interactions. Pharmacol Biochem Behav 1990, 37, 95.
         | Pharmacological characterization of ear-scratch response in mice as a behavioral model for selective 5-HT2-receptor agonists and evidence for 5-HT1B- and 5-HT2-receptor interactions.Crossref | GoogleScholarGoogle Scholar |

[31]  NA Darmani, BR Martin, RA Glennon, Withdrawal from chronic treatment with (±)-DOI causes super-sensitivity to 5-HT2 receptor-induced head-twitch behaviour in mice. Eur J Pharmacol 1990, 186, 115.
         | Withdrawal from chronic treatment with (±)-DOI causes super-sensitivity to 5-HT2 receptor-induced head-twitch behaviour in mice.Crossref | GoogleScholarGoogle Scholar |

[32]  Glennon RA, Young R. Drug discrimination: applications to medicinal chemistry and drug studies. Wiley; 2011.

[33]  R Young, JA Rosecrans, RA Glennon, Further studies on the dose-dependent stimulus properties of 5-methoxy-N,N-dimethyltryptamine. Pharmacol Biochem Behav 1986, 25, 1207.
         | Further studies on the dose-dependent stimulus properties of 5-methoxy-N,N-dimethyltryptamine.Crossref | GoogleScholarGoogle Scholar |

[34]  IP Stolerman, E Childs, MM Ford, KA Grant, Role of training dose in drug discrimination: a review. Behav Pharmacol 2011, 22, 415.
         | Role of training dose in drug discrimination: a review.Crossref | GoogleScholarGoogle Scholar |

[35]  RA Glennon, R Young, JA Rosecrans, Antagonism of the effects of the hallucinogen DOM and the purported 5-HT agonist quipazine by 5-HT2 antagonists. Eur J Pharmacol 1983, 91, 189.
         | Antagonism of the effects of the hallucinogen DOM and the purported 5-HT agonist quipazine by 5-HT2 antagonists.Crossref | GoogleScholarGoogle Scholar |

[36]  FC Colpaert, CJ Niemegeers, PA Janssen, A drug discrimination analysis of lysergic acid diethylamide (LSD): in vivo agonist and antagonist effects of purported 5-hydroxytryptamine antagonists and of pirenperone, a LSD-antagonist. J Pharmacol Exp Ther 1982, 221, 206.

[37]  JB Appel, PM Callahan, Involvement of 5-HT receptor subtypes in the discriminative stimulus properties of mescaline. Eur J Pharmacol 1989, 159, 41.
         | Involvement of 5-HT receptor subtypes in the discriminative stimulus properties of mescaline.Crossref | GoogleScholarGoogle Scholar |

[38]  RA Glennon, AE Hauck, Mechanistic studies on DOM as a discriminative stimulus. Pharmacol Biochem Behav 1985, 23, 937.
         | Mechanistic studies on DOM as a discriminative stimulus.Crossref | GoogleScholarGoogle Scholar |

[39]  CT Egan, K Herrick-Davis, K Miller, RA Glennon, M Teitler, Agonist activity of LSD and lisuride at cloned 5HT2A and 5HT2C receptors. Psychopharmacology (Berl) 1998, 136, 409.
         | Agonist activity of LSD and lisuride at cloned 5HT2A and 5HT2C receptors.Crossref | GoogleScholarGoogle Scholar |

[40]  Glennon RA. Classical hallucinogens. In: Lin GC, Glennon RA, editors. Hallucinogens: an update. U.S. Government Printing Office; 1994. pp. 4–32.

[41]  PM Callahan, JB Appel, Differentiation between the stimulus effects of (+)-lysergic acid diethylamide and lisuride using a three-choice, drug discrimination procedure. Psychopharmacology (Berl) 1990, 100, 13.
         | Differentiation between the stimulus effects of (+)-lysergic acid diethylamide and lisuride using a three-choice, drug discrimination procedure.Crossref | GoogleScholarGoogle Scholar |

[42]  AL Halberstadt, M Chatha, AK Klein, J Wallach, SD Brandt, Correlation between the potency of hallucinogens in the mouse head-twitch response assay and their behavioral and subjective effects in other species. Neuropharmacology 2020, 167, 107933.
         | Correlation between the potency of hallucinogens in the mouse head-twitch response assay and their behavioral and subjective effects in other species.Crossref | GoogleScholarGoogle Scholar |

[43]  FJ White, DM Kuhn, JB Appel, Discriminative stimulus properties of quipazine. Neuropharmacology 1977, 16, 827.
         | Discriminative stimulus properties of quipazine.Crossref | GoogleScholarGoogle Scholar |

[44]  FJ White, JB Appel, DM Kuhn, Discriminative stimulus properties of quipazine: direct serotonergic mediation. Neuropharmacology 1979, 18, 143.
         | Discriminative stimulus properties of quipazine: direct serotonergic mediation.Crossref | GoogleScholarGoogle Scholar |

[45]  JC Winter, Quipazine-induced stimulus control in the rat. Psychopharmacology (Berl) 1979, 60, 265.
         | Quipazine-induced stimulus control in the rat.Crossref | GoogleScholarGoogle Scholar |

[46]  MD Schechter, JT Concannon, Dopaminergic activity of quipazine. Pharmacol Biochem Behav 1982, 17, 393.
         | Dopaminergic activity of quipazine.Crossref | GoogleScholarGoogle Scholar |

[47]  FJ White, JB Appel, Lysergic acid diethylamide (LSD) and lisuride: differentiation of their neuropharmacological actions. Science 1982, 216, 535.
         | Lysergic acid diethylamide (LSD) and lisuride: differentiation of their neuropharmacological actions.Crossref | GoogleScholarGoogle Scholar |

[48]  JX Li, KC Rice, CP France, Discriminative stimulus effects of 1-(2,5-dimethoxy-4-methylphenyl)-2-aminopropane in rhesus monkeys. J Pharmacol Exp Ther 2008, 324, 827.
         | Discriminative stimulus effects of 1-(2,5-dimethoxy-4-methylphenyl)-2-aminopropane in rhesus monkeys.Crossref | GoogleScholarGoogle Scholar |

[49]  RL Friedman, RJ Barrett, E Sanders-Bush, Discriminative stimulus properties of quipazine: mediation by serotonin2 binding sites. J Pharmacol Exp Ther 1984, 228, 628.

[50]  RL Smith, PJ Gresch, RJ Barrett, E Sanders-Bush, Stimulus generalization by fenfluramine in a quipazine-ketanserin drug discrimination is not dependent on indirect serotonin release. Pharmacol Biochem Behav 2002, 72, 77.
         | Stimulus generalization by fenfluramine in a quipazine-ketanserin drug discrimination is not dependent on indirect serotonin release.Crossref | GoogleScholarGoogle Scholar |

[51]  Glennon RA. Site-selective serotonin agonists as discriminative stimuli. In: Colpaert FC, Balster RL, editors. Transduction Mechanisms of Drug Stimuli. Psychopharmacology Series. Vol. 4. Springer Berlin, Heidelberg; 1988; pp. 15–31.

[52]  Glennon RA. Discriminative stimulus properties of hallucinogens and related designer drugs. In: Glennon RA, Järbe TUC, Frankenheim J, editors. Drug discrimination: applications to drug abuse research. U.S. Government Printing Office DHHS Publication ADM92-1878; 1991. pp. 25–44.

[53]  RA Glennon, RM Slusher, RA Lyon, M Titeler, JD McKenney, 5-HT1 and 5-HT2: binding characteristics of some quipazine analogs. J Med Chem 1986, 29, 2375.
         | 5-HT1 and 5-HT2: binding characteristics of some quipazine analogs.Crossref | GoogleScholarGoogle Scholar |

[54]  JW McKearney, Effects of serotonin agonists on operant behavior in the squirrel monkey: quipazine, MK-212, trifluoromethylphenylpiperazine, and chlorophenylpiperazine. Pharmacol Biochem Behav 1990, 35, 181.
         | Effects of serotonin agonists on operant behavior in the squirrel monkey: quipazine, MK-212, trifluoromethylphenylpiperazine, and chlorophenylpiperazine.Crossref | GoogleScholarGoogle Scholar |

[55]  JW McKearney, Serotonin-antagonist effects of 1-(1-naphthyl)piperazine on operant behavior of squirrel monkeys. Neuropharmacology 1989, 28, 817.
         | Serotonin-antagonist effects of 1-(1-naphthyl)piperazine on operant behavior of squirrel monkeys.Crossref | GoogleScholarGoogle Scholar |

[56]  RA Glennon, R Young, M Dukat, 5-HT3 agonist 2-methylserotonin as a training drug in drug discrimination studies. Pharmacol Biochem Behav 1992, 41, 361.
         | 5-HT3 agonist 2-methylserotonin as a training drug in drug discrimination studies.Crossref | GoogleScholarGoogle Scholar |

[57]  R De La Garza II, PM Callahan, KA Cunningham, Detailed investigations of 5-HT3 compounds in a drug discrimination model. Pharmacol Biochem Behav 1996, 54, 533.
         | Detailed investigations of 5-HT3 compounds in a drug discrimination model.Crossref | GoogleScholarGoogle Scholar |

[58]  M Dukat, R Young, NN Darmani, B Ahmed, RA Glennon, The 5-HT3 agent N-(3-chlorophenyl)guanidine (MD-354) serves as a discriminative stimulus in rats and displays partial agonist character in a shrew emesis assay. Psychopharmacology (Berl) 2000, 150, 200.
         | The 5-HT3 agent N-(3-chlorophenyl)guanidine (MD-354) serves as a discriminative stimulus in rats and displays partial agonist character in a shrew emesis assay.Crossref | GoogleScholarGoogle Scholar |

[59]  M Dukat, AA Abdel-Rahman, AM Ismaiel, S Ingher, M Teitler, L Gyermek, RA Glennon, Structure-activity relationships for the binding of arylpiperazines and arylbiguanides at 5-HT3 serotonin receptors. J Med Chem 1996, 39, 4017.
         | Structure-activity relationships for the binding of arylpiperazines and arylbiguanides at 5-HT3 serotonin receptors.Crossref | GoogleScholarGoogle Scholar |

[60]  JB Malick, E Doren, A Barnett, Quipazine-induced head-twitch in mice. Pharmacol Biochem Behav 1977, 6, 325.
         | Quipazine-induced head-twitch in mice.Crossref | GoogleScholarGoogle Scholar |

[61]  M de la Fuente Revenga, UH Shah, N Nassehi, AM Jaster, P Hemanth, S Sierra, M Dukat, J González-Maeso, Psychedelic-like properties of quipazine and its structural analogues in mice. ACS Chem Neurosci 2021, 12, 831.
         | Psychedelic-like properties of quipazine and its structural analogues in mice.Crossref | GoogleScholarGoogle Scholar |

[62]  RW Fuller, HD Snoody, NR Mason, BB Molloy, Effect of 1-(m-trifluoromethylphenyl)-piperazine on 3H-serotonin binding to membranes from rat brain in vitro and on serotonin turnover in rat brain in vivo. Eur J Pharmacol 1978, 52, 11.
         | Effect of 1-(m-trifluoromethylphenyl)-piperazine on 3H-serotonin binding to membranes from rat brain in vitro and on serotonin turnover in rat brain in vivo.Crossref | GoogleScholarGoogle Scholar |

[63]  C Egan, E Grinde, A Dupre, BL Roth, M Hake, M Teitler, K Herrick-Davis, Agonist high and low affinity state ratios predict drug intrinsic activity and a revised ternary complex mechanism at serotonin 5-HT2A and 5-HT2C receptors. Synapse 2000, 35, 144.
         | Agonist high and low affinity state ratios predict drug intrinsic activity and a revised ternary complex mechanism at serotonin 5-HT2A and 5-HT2C receptors.Crossref | GoogleScholarGoogle Scholar |

[64]  Jones CB, Hemanth P, Younkin J, González-Maeso J, Dukat M. Re-visiting binding modes of quipazine and 2-NP at recent 5-HT2A receptor X-ray structures. The 2nd Annual Psychedelic Therapeutics and Drug Development Conference; 23–24 May, 2022; Washington, DC, USA. [Poster presentation]

[65]  AR Knight, A Misra, K Quirk, K Benwell, D Revell, G Kennett, M Bickerdike, Pharmacological characterisation of the agonist radioligand binding site of 5-HT2A, 5-HT2B and 5-HT2C receptors. Naunyn Schmiedebergs Arch Pharmacol 2004, 370, 114.
         | Pharmacological characterisation of the agonist radioligand binding site of 5-HT2A, 5-HT2B and 5-HT2C receptors.Crossref | GoogleScholarGoogle Scholar |

[66]  KA Berg, S Maayani, J Goldfarb, C Scaramellini, P Leff, WP Clarke, Effector pathway-dependent relative efficacy at serotonin type 2A and 2C receptors: evidence for agonist-directed trafficking of receptor stimulus. Mol Pharmacol 1998, 54, 94.
         | Effector pathway-dependent relative efficacy at serotonin type 2A and 2C receptors: evidence for agonist-directed trafficking of receptor stimulus.Crossref | GoogleScholarGoogle Scholar |

[67]  XP Huang, V Setola, PN Yadav, JA Allen, SC Rogan, BJ Hanson, C Revankar, M Robers, C Doucette, BL Roth, Parallel functional activity profiling reveals valvulopathogens are potent 5-hydroxytryptamine(2B) receptor agonists: implications for drug safety assessment. Mol Pharmacol 2009, 76, 710.
         | Parallel functional activity profiling reveals valvulopathogens are potent 5-hydroxytryptamine(2B) receptor agonists: implications for drug safety assessment.Crossref | GoogleScholarGoogle Scholar |

[68]  NA Sharif, EHF Wong, DN Loury, E Stefanich, AD Michel, RM Eglen, RL Whiting, Characteristics of 5-HT3 binding sites in NG108-15, NCB-20 neuroblastoma cells and rat cerebral cortex using [3H]-quipazine and [3H]-GR65630 binding. Br J Pharmacol 1991, 102, 919.
         | Characteristics of 5-HT3 binding sites in NG108-15, NCB-20 neuroblastoma cells and rat cerebral cortex using [3H]-quipazine and [3H]-GR65630 binding.Crossref | GoogleScholarGoogle Scholar |

[69]  RA Glennon, AE-KM Ismaiel, BM McCarthy, SJ Peroutka, Binding of arylpiperazines to 5-HT3 serotonin receptors: results of a structure-affinity study. Eur J Pharmacol 1989, 168, 387.
         | Binding of arylpiperazines to 5-HT3 serotonin receptors: results of a structure-affinity study.Crossref | GoogleScholarGoogle Scholar |

[70]  A Cappelli, G Giuliani, A Gallelli, S Valenti, M Anzini, L Mennuni, F Makovec, A Cupello, S Vomero, Structure-affinity relationship studies on arylpiperazine derivatives related to quipazine as serotonin transporter ligands. Molecular basis of the selectivity SERT/5HT3 receptor. Bioorg Med Chem 2005, 13, 3455.
         | Structure-affinity relationship studies on arylpiperazine derivatives related to quipazine as serotonin transporter ligands. Molecular basis of the selectivity SERT/5HT3 receptor.Crossref | GoogleScholarGoogle Scholar |

[71]  CA Brady, IM Stanford, I Ali, L Lin, JM Williams, AE Dubin, AG Hope, NM Barnes, Pharmacological comparison of human homomeric 5-HT3A receptors versus heteromeric 5-HT3A/3B receptors. Neuropharmacology 2001, 41, 282.
         | Pharmacological comparison of human homomeric 5-HT3A receptors versus heteromeric 5-HT3A/3B receptors.Crossref | GoogleScholarGoogle Scholar |

[72]  Shulgin AT, Manning T, Daley PF. The Shulgin index: psychedelic phenethylamines and related compounds. Transform Press; 2011. p. 34.