title: Effect of Hallucinogens on Unconditioned Behavior.
abstract: Because of the ethical and regulatory hurdles associated with human studies, much of what is known about the psychopharmacology of hallucinogens has been derived from animal models. However, developing reliable animal models has proven to be a challenging task due to the complexity and variability of hallucinogen effects in humans. This chapter focuses on three animal models that are frequently used to test the effects of hallucinogens on unconditioned behavior: head twitch response (HTR), prepulse inhibition of startle (PPI), and exploratory behavior. The HTR has demonstrated considerable utility in the neurochemical actions of hallucinogens. However, the latter two models have clearer conceptual bridges to human phenomenology. Consistent with the known mechanism of action of hallucinogens in humans, the behavioral effects of hallucinogens in rodents are mediated primarily by activation of 5-HT2Areceptors. There is evidence, however, that other receptors may play secondary roles. The structure-activity relationships (SAR) of hallucinogens are reviewed in relation to each model, with a focus on the HTR in rats and mice.
authors.affiliation: Department of Psychiatry, University of California San Diego, La Jolla, CA, 92093-0804, USA. ahalberstadt@ucsd.edu.|Research Service, VA San Diego Healthcare System, San Diego, CA, USA. ahalberstadt@ucsd.edu.
authors.forename: Adam L
authors.initials: AL
authors.lastname: Halberstadt
authors.affiliation: Department of Psychiatry, University of California San Diego, La Jolla, CA, 92093-0804, USA.|Research Service, VA San Diego Healthcare System, San Diego, CA, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Geyer
mesh_terms: D000818:Animals; D001519:Behavior / Q000187:drug effects*; D001522:Behavior, Animal / Q000187:drug effects*; D005106:Exploratory Behavior / Q000187:drug effects; D006213:Hallucinogens / Q000494:pharmacology*; D006801:Humans; D051379:Mice; D023421:Models, Animal; D051381:Rats; D055139:Sensory Gating / Q000187:drug effects; D058826:Serotonin 5-HT2 Receptor Agonists / Q000494:pharmacology
chemical_list: D006213:Hallucinogens; D058826:Serotonin 5-HT2 Receptor Agonists
keywords: 1-methylpsilocin; 25CN-NBOH; 25I-NBOMe; 5-HT2C receptor; DOI; LSD; Lisuride; Locomotor activity; Lysergic acid diethylamide; M100907; Mescaline; Mouse; Psilocybin; Psychedelic; Quipazine; Rat; SB-242,084; Wet dog shake