title: The rewarding properties of methamphetamine in an invertebrate model of drug addiction.
abstract: The rewarding properties of drugs in the mammalian system depend on their ability to activate appetitive motivational states. The associated underlying mechanism is strongly conserved in evolution and invertebrates have recently emerged as a powerful new model in addiction research. The natural reward system in crayfish has surprisingly proven sensitive to human drugs of abuse, providing a new model for research into the basic biological mechanisms of drug addiction. In this study, we examined the presence of natural reward systems in crayfish, and then characterized its sensitivity to 2.5 μg/g, 5.0 μg/g and 10.0 μg/g doses of methamphetamine (METH). Using the conditioned place preference (CPP) paradigm, we demonstrated that irrespective of the number of doses of METH injected into the pericardial system, crayfish seek out a particular tactile environment that had previously been paired with the METH. This study demonstrates that crayfish offer a comparative and complementary approach in addiction research. It contributes an evolutionary context to our understanding of a key component in learning and of natural reward as an important life-sustaining process.
authors.affiliation: Department of Biology, North Greenville University, Tigerville, SC 29688, USA.
authors.forename: Adebobola
authors.initials: A
authors.lastname: Imeh-Nathaniel
authors.affiliation: Department of Health Sciences, East Tennessee State University, Johnson City, TN 37614, USA.
authors.forename: Adekunle
authors.initials: A
authors.lastname: Adedeji
authors.affiliation: Department of Biological Sciences, Bowling Green State University, Life Sciences Bldg., Bowling Green, OH 43403, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Huber
authors.affiliation: University of South Carolina, School of Medicine-Greenville, 607 Grove Road, Greenville, SC 29605, USA. Electronic address: nathanit@greenvillemed.sc.edu.
authors.forename: Thomas I
authors.initials: TI
authors.lastname: Nathaniel
mesh_terms: D000818:Animals; D003400:Astacoidea / Q000187:drug effects*; D003213:Conditioning, Psychological; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D008297:Male; D008694:Methamphetamine / Q000008:administration & dosage / Q000494:pharmacology*; D017551:Microdialysis; D009042:Motivation; D012201:Reward; D013037:Spatial Behavior / Q000187:drug effects; D019966:Substance-Related Disorders
chemical_list: D008694:Methamphetamine
keywords: Addiction; CPP; Crayfish; Drug; Invertebrate; METH; Reward