Browsing by Subject "Limited-access"

Now showing 1 - 3 of 3
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    Developing a model of limited-access nicotine consumption in C57Bl/6J mice
    (Elsevier, 2016-09) Kasten, C.R.; Frazee, A.M.; Boehm, S.L.; Psychology, School of Science
    Although United States smoking rates have been on the decline over the past few decades, cigarette smoking still poses a critical health and economic threat. Very few treatment options for smoking exist, and many of them do not lead to long-term abstinence. Preclinical models are necessary for understanding the effects of nicotine and developing treatments. Current self-administration models of nicotine intake may require surgical procedures and often result in low levels of intake. Further, they do not lend themselves to investigating treatments. The current study sought to develop a limited-access model of nicotine intake using the Drinking-in-the-Dark paradigm, which results in high levels of binge-like ethanol consumption that can be pharmacologically manipulated. The present study found that mice will consume nicotine under a range of parameters. Intakes under the preferred condition of 0.14 mg/ml nicotine in 0.2% saccharin reached over 6 mg/kg in two hours and were reduced by an injection of R(+)-baclofen. Mecamylamine did not significantly affect nicotine consumption. As nicotine and ethanol are often co-abused, nicotine intake was also tested in the presence of ethanol. When presented in the same bottle, mice altered nicotine intake under various concentrations to maintain consistent levels of ethanol intake. When nicotine and ethanol were presented in separate bottles, mice greatly reduced their nicotine intake while maintaining ethanol intake. In conclusion, these studies characterize a novel model of limited-access nicotine intake that can be pharmacologically manipulated.
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    "Drinking in the Dark" (DID): a simple mouse model of binge-like alcohol intake
    (Wiley, 2014-07) Thiele, Todd E.; Crabbe, John C.; Boehm, Stephen L. II; Psychology, School of Science
    One of the greatest challenges that scientists face when studying the neurobiology and/or genetics of alcohol (ethanol) consumption is that most preclinical animal models do not voluntarily consume enough ethanol to achieve pharmacologically meaningful blood ethanol concentrations (BECs). Recent rodent models have been developed that promote binge-like levels of ethanol consumption associated with high BECs (i.e., ≥100 mg/dl). This unit describes procedures for an animal model of binge-like ethanol drinking which has come to be called "drinking in the dark" (DID). The "basic" variation of DID involves replacing the water bottle with a bottle containing 20% ethanol for 2 to 4 hr, beginning 3 hr into the dark cycle, on cages of singly-housed C57BL/6J mice. Using this procedure, mice typically consume enough ethanol to achieve BECs >100 mg/dl and to exhibit behavioral evidence of intoxication. An alternative two-bottle (ethanol and water) procedure is also described.
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    Rodent models and mechanisms of voluntary binge-like ethanol consumption: Examples, opportunities, and strategies for preclinical research
    (Elsevier, 2016-02-04) Fritz, Brandon M.; Boehm II, Stephen L.; Department of Psychology, School of Science
    Binge ethanol consumption has widespread negative consequences for global public health. Rodent models offer exceptional power to explore the neurobiology underlying and affected by binge-like drinking as well as target potential prevention, intervention, and treatment strategies. An important characteristic of these models is their ability to consistently produce pharmacologically-relevant blood ethanol concentration. This review examines the current available rodent models of voluntary, pre-dependent binge-like ethanol consumption and their utility in various research strategies. Studies have demonstrated that a diverse array of neurotransmitters regulate binge-like drinking, resembling some findings from other drinking models. Furthermore, repeated binge-like drinking recruits neuroadaptive mechanisms in mesolimbocortical reward circuitry. New opportunities that these models offer in the current context of mechanistic research are also discussed.