Behavioral effects of amphetamine in streptozotocin-treated rats

Abstract

Experimentally-induced diabetes can modify the behavioral and neurochemical effects of drugs acting on dopamine systems, possibly through insulin-related regulation of dopamine transporter activity. In this study, several behavioral procedures were used to examine possible changes in sensitivity to amphetamine and other drugs in rats rendered diabetic by a single injection of streptozotocin. Conditioned place preference developed to food (Froot Loops ® ) in both control and diabetic rats, demonstrating that conditioned place preference with tactile stimuli can occur in streptozotocin-treated rats. Baseline locomotion was lower in streptozotocin-treated as compared to control rats, although amphetamine significantly increased locomotion in all rats. Conditioned place preference developed to amphetamine regardless of whether rats had received streptozotocin or saline. A second study compared the potency of drugs to decrease lever pressing maintained by food, before and after streptozotocin treatment. Gamma-hydroxybutyrate and amphetamine were less potent after streptozotocin while the potency of raclopride, quinpirole, ketamine, haloperidol and cocaine was not significantly changed by streptozotocin. While markedly affecting locomotion, body weight and blood glucose, streptozotocin only modestly affected sensitivity to the behavioral effects of amphetamine and other drugs; these results fail to confirm previous reports of decreased behavioral actions of stimulants in diabetic rats.

Enhanced nicotine self-administration and suppressed dopaminergic systems in a rat model of diabetes

“…STZ treatment has been shown to decrease D2 receptor sensitivity in behavioral assays assessing catalepsy, yawning, and locomotor activity (Sevak et al, 2005, 2007); although no change in sensitivity of D2 receptors to food reward have been found (Sevak et al, 2008). Studies evaluating the rewarding effects of amphetamine in STZ-treated rats have produced mixed results.…”

“…Studies evaluating the rewarding effects of amphetamine in STZ-treated rats have produced mixed results. For example, Galici et al (2003) demonstrated that STZ-treated rats displayed a reduction in amphetamine IVSA, whereas Sevak et al (2008) found that STZ did not alter place preference produced by amphetamine. These results contrast our finding that STZ-treated rats displayed an increase in the rewarding effects of nicotine.…”

Enhanced vulnerability to tobacco use in persons with diabetes: A behavioral and neurobiological framework

“…For example, STZ-treated rats display a decrease in the locomotor activating effects of amphetamine, as well as a decrease in amphetamine intake (Galici et al, 2003b;Sevak et al, 2008), although no change in amphetamine CPP was shown (Sevak et al, 2008). Also, diabetic rats do not display changes in cocaine intake (Galici et al, 2003a) but show a decrease in cocaine-induced CPP .…”

Central Dopaminergic Activity Influences Metabolic Parameters in Healthy Men

“…Studies on rats have shown that chronic food restriction inhibits the function of DAT [28]. Williams et al [29] found significantly diminished levels and function of DAT in streptozotocin-induced hypoinsulinemic rats, and Daws et al [30] reported decreased DAT function in diet-induced obese states of brain insulin-resistant rats.…”