Substitutability of nicotine and sucrose in rats: A behavioral economic analysis.

Despite considerable evidence suggesting that sweet foods are a substitute for nicotine in humans, no formal behavioral economic analysis of this interrelationship has been conducted in nonhumans. The purpose of the present study was to examine this phenomenon in rats using concurrent schedules of sucrose pellet, chow pellet, and nicotine reinforcer delivery. Rats responded on separate levers that delivered sucrose pellets, chow pellets, or nicotine infusions under concurrent fixed-ratio (FR) 1 schedules for each commodity within a closed economy.

Effects of isolated tobacco alkaloids and tobacco products on deprivation-induced food intake and meal patterns in rats.

The ability of smoking to reduce body weight serves as motivation for continued smoking. It is unclear to what extent non-nicotine constituents in cigarettes are contributing to the weight-reducing effect of smoking. The purpose of the current study was to examine the effects of nicotine and four minor tobacco alkaloids (nornicotine, cotinine, anatabine, and anabasine) on food intake, one of the key regulators of body weight.

Neuromodulation of orexin neurons reduces diet-induced adiposity.

Background/objectives: Low levels of orexin are associated with obesity and reduced physical activity in humans and animals.

Subjects/methods: Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) selectively activated orexin neurons in mouse lateral hypothalamus (LH) to measure effects on spontaneous physical activity (SPA). DREADD targeting was achieved by stereotaxic injection of AAV vectors into caudal lateral LH of heterozygous orexin-Cre or C57/B6J mice.

Orexin activation counteracts decreases in nonexercise activity thermogenesis (NEAT) caused by high-fat diet.

Overweight and obesity result from an imbalance between caloric intake and energy expenditure, including expenditure from spontaneous physical activity (SPA). Changes in SPA and resulting changes in non-exercise activity thermogenesis (NEAT) likely interact with diet to influence risk for obesity. However, previous research on the relationship between diet, physical activity, and energy expenditure has been mixed.

The effects of nicotine self-administration and withdrawal on concurrently available chow and sucrose intake in adult male rats.

Carbohydrate intake, preference, and taste thresholds may be altered in current and former cigarette smokers, which may mediate weight gain and risk for obesity in individuals who quit smoking. Attempts to model these effects in rodents have primarily used noncontingent nicotine administration. The purpose of this research was to characterize changes in chow and sucrose intake in rats during a 23-h access model of i.