The Effects of Eating a High Fat Diet on Sensitivity of Rats to Methamphetamine-Induced Conditioned Place Preference
Eating a high fat diet causes several negative health consequences, including dysfunction to dopamine systems. For example, eating a high fat diet enhances sensitivity of rats to methamphetamine-induced locomotor sensitization. However, it is not known if sensitivity to other (i.e., the rewarding) effects of methamphetamine are similarly enhanced in rats eating a high fat diet. Females are more sensitive than males to the behavioral effects of stimulants in general, and therefore might also be particularly vulnerable to the effects of diet on the rewarding effects of stimulant drugs. To test the hypothesis that eating high fat chow enhances sensitivity of rats to the rewarding effects of methamphetamine, female and male Sprague-Dawley rats were fed standard (17% kcal from fat) or high fat chow (60% kcal from fat) for 4 weeks prior to conditioned place preference (CPP) training, using a biased design. Before training, rats were given free access to both sides of the chamber in order to determine a side preference. Rats were trained on alternating days with saline or methamphetamine (0.1, 0.32 and 1.0 mg/kg, i.p.) with drug conditioned in the initially non-preferred side. Methamphetamine induced a significant CPP among female rats at the two largest doses (0.32 and 1.0 mg/kg; at least compared to the smaller dose [0.1 mg/kg], in the absence of a saline conditioned control group). While the two largest doses of methamphetamine also induced a significant CPP among male rats when compared to the saline conditioned group, the smallest dose of methamphetamine (0.1 mg/kg) resulted in preference scores that did not differ significantly from male rats conditioned with saline. Future studies will examine a wider range of doses of methamphetamine, as well as other addiction-relevant behaviors (i.e., self-administration).
Galindo, Kayla Irene, "The Effects of Eating a High Fat Diet on Sensitivity of Rats to Methamphetamine-Induced Conditioned Place Preference" (2020). ETD Collection for University of Texas, El Paso. AAI28262096.