1. Striatal dopamine D1-type receptor availability: no difference from control but association with cortical thickness in methamphetamine users
- Author
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Okita, K, Morales, AM, Dean, AC, Johnson, MC, Lu, V, Farahi, J, Mandelkern, MA, and London, ED
- Subjects
Biological Psychology ,Pharmacology and Pharmaceutical Sciences ,Biomedical and Clinical Sciences ,Psychology ,Substance Misuse ,Drug Abuse (NIDA only) ,Neurosciences ,Methamphetamine ,2.1 Biological and endogenous factors ,Aetiology ,Adult ,Amphetamine-Related Disorders ,Case-Control Studies ,Caudate Nucleus ,Corpus Striatum ,Dopamine ,Female ,Gray Matter ,Humans ,Magnetic Resonance Imaging ,Male ,Nucleus Accumbens ,Positron-Emission Tomography ,Receptors ,Dopamine D1 ,Receptors ,Dopamine D2 ,Young Adult ,Biological Sciences ,Medical and Health Sciences ,Psychology and Cognitive Sciences ,Psychiatry ,Clinical sciences ,Biological psychology ,Clinical and health psychology - Abstract
Chronic methamphetamine use poses potentially devastating consequences for directly affected individuals and for society. Lower dopamine D2-type receptor availability has been observed in striata of methamphetamine users as compared with controls, but an analogous comparison of D1-type receptors has been conducted only on post-mortem material, with no differences in methamphetamine users from controls in the caudate nucleus and putamen and higher D1-receptor density in the nucleus accumbens. Released from neurons when methamphetamine is self-administered, dopamine binds to both D1- and D2-type receptors in the striatum, with downstream effects on cortical activity. Thus, both receptor subtypes may contribute to methamphetamine-induced alterations in cortical morphology and behavior. In this study, 21 methamphetamine-dependent subjects and 23 healthy controls participated in positron emission tomography and structural magnetic resonance imaging for assessment of striatal D1- and D2-type receptor availability and cortical gray-matter thickness, respectively. Although D2-type receptor availability (BPnd) was lower in the methamphetamine group, as shown previously, the groups did not differ in D1-type BPnd. In the methamphetamine group, mean cortical gray-matter thickness was negatively associated with cumulative methamphetamine use and craving for the drug. Striatal D1-type but not D2-type BPnd was negatively associated with global mean cortical gray-matter thickness in the methamphetamine group, but no association was found between gray-matter thickness and BPnd for either dopamine receptor subtype in the control group. These results suggest a role of striatal D1-type receptors in cortical adaptation to chronic methamphetamine use. more...
- Published
- 2018