Bridget W Brox1, Bart A Ellenbroek2. 1. School of Psychology, Behavioural Neurogenetics Group, Victoria University of Wellington, PO Box 600, Wellington, 6041, New Zealand. 2. School of Psychology, Behavioural Neurogenetics Group, Victoria University of Wellington, PO Box 600, Wellington, 6041, New Zealand. Bart.Ellenbroek@vuw.ac.nz.
Abstract
BACKGROUND: Despite ongoing study and research to better understand drug addiction, it continues to be a heavy burden. Only a small percentage of individuals who take drugs of abuse go on to develop addiction. However, there is growing evidence to suggest that a reduction in the serotonin transporter may play an important role for those that transition to compulsive drug taking. Studies have demonstrated that reduced serotonin transporter function potentiates self-administration of psychostimulant drugs ("ecstasy," MDMA; cocaine); however, additional research revealed no differences between genotypes when the opioid heroin was self-administered. These results suggest that a reduction in the serotonin transporter may confer susceptibility to the development of addiction to some classes of drugs but not others. Importantly, the mechanism underlying facilitated psychostimulant self-administration is currently unknown. METHODS: Therefore, to continue investigating the relationship between compromised serotonergic function and different classes of drugs, a series of experiments was conducted investigating locomotor activity (LMA) and conditioned taste aversion (CTA) in the serotonin transporter knockout (SERT KO) rat model. RESULTS: MDMA-induced hyperactivity was reduced, while MDMA-induced CTA was enhanced, in SERT KO rats. However, there were no genotype differences in heroin-induced behaviours. CONCLUSIONS: These results reinforce the idea that a reduction in the serotonin transporter drives differential effects between disparate classes of drugs of abuse.
BACKGROUND: Despite ongoing study and research to better understand drug addiction, it continues to be a heavy burden. Only a small percentage of individuals who take drugs of abuse go on to develop addiction. However, there is growing evidence to suggest that a reduction in the serotonin transporter may play an important role for those that transition to compulsive drug taking. Studies have demonstrated that reduced serotonin transporter function potentiates self-administration of psychostimulant drugs ("ecstasy," MDMA; cocaine); however, additional research revealed no differences between genotypes when the opioid heroin was self-administered. These results suggest that a reduction in the serotonin transporter may confer susceptibility to the development of addiction to some classes of drugs but not others. Importantly, the mechanism underlying facilitated psychostimulant self-administration is currently unknown. METHODS: Therefore, to continue investigating the relationship between compromised serotonergic function and different classes of drugs, a series of experiments was conducted investigating locomotor activity (LMA) and conditioned taste aversion (CTA) in the serotonin transporter knockout (SERT KO) rat model. RESULTS:MDMA-induced hyperactivity was reduced, while MDMA-induced CTA was enhanced, in SERT KO rats. However, there were no genotype differences in heroin-induced behaviours. CONCLUSIONS: These results reinforce the idea that a reduction in the serotonin transporter drives differential effects between disparate classes of drugs of abuse.
Authors: J D A Olivier; M G C Van Der Hart; R P L Van Swelm; P J Dederen; J R Homberg; T Cremers; P M T Deen; E Cuppen; A R Cools; B A Ellenbroek Journal: Neuroscience Date: 2008-01-01 Impact factor: 3.590
Authors: Ahmad R Hariri; Venkata S Mattay; Alessandro Tessitore; Bhaskar Kolachana; Francesco Fera; David Goldman; Michael F Egan; Daniel R Weinberger Journal: Science Date: 2002-07-19 Impact factor: 47.728