Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.107 (DAT)
 1,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Insulin affects brain reward pathways and there is converging evidence that this occurs through insulin regulation of the dopamine (DA) transporter (DAT). In rats made hypoinsulinemic by fasting, synaptosomal DA uptake is reduced. Interestingly, [3H]DA uptake is increased in hypoinsulinemic rats with a history of amphetamine self-administration. The possibility that amphetamine and insulin act in concert to regulate DAT activity prompted this study. Here we show that [3H]DA uptake, measured in vitro and clearance of exogenously applied DA in vivo, is significantly reduced in rats made hypoinsulinemic by a single injection of streptozotocin. Strikingly, amphetamine (1.78 mg/kg, given every other day for 8 days) restored DA clearance in streptozotocin-treated rats but was without effect on DA clearance in saline-treated rats. Basal locomotor activity of streptozotocin-treated rats was lower compared to control rats; however, in streptozotocin-treated rats, hyperlocomotion induced by amphetamine increased over successive amphetamine injections. In saline-treated rats the locomotor stimulant effect of amphetamine remained stable across the four amphetamine injections. These results provide exciting new evidence that actions of amphetamine on DA neurotransmission are insulin-dependent and further suggest that exposure to amphetamine may cause long-lasting changes in DAT function.
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PMID:Deficits in dopamine clearance and locomotion in hypoinsulinemic rats unmask novel modulation of dopamine transporters by amphetamine. 1599 64

Diabetes mellitus is a chronic illness that has been associated with the decrease of insulin in type I diabetes. Insulin has an impact not only on the direct control of food intake and plasma glucose levels, but also on brain pathways associated with reward. It affects brain reward pathways through regulation of the dopamine (DA) transporter (DAT). Moreover, it has been found to affect the ability of drugs that target the DA system. In the present study, the effects of streptozotocin (STZ)-induced diabetes on the acquisition (development) and maintenance of morphine-induced conditioned place preference (CPP) were investigated in rats. Forty adult male Albino Wistar rats were used in these experiments. For induction of diabetes, STZ was administered at a dose of 60 mg/kg. After seven days, the CPP paradigm was done; conditioning score and locomotor activity were recorded by Ethovision software. The results showed that diabetes significantly increased the magnitude of conditioning scores, acquisition of morphine-induced CPP in compared to naive animals (P<0.05). Moreover, in the diabetic group, there were significant differences among conditioning scores in the post-conditioning phase and the last four days (7th-10th), but these differences elongated up to 10 days after the CPP protocol while the extinction period was eight days in the naive group. Our findings indicated that the magnitude and maintenance of morphine rewarding properties have been changed in STZ-induced diabetic animals. It seems that a level of insulin and their receptors are involved in the development and maintenance of morphine-induced CPP in the rats.
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PMID:Streptozotocin-induced diabetes affects the development and maintenance of morphine reward in rats. 2354 8