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NATIONAL INSTITUTE ON DRUG ABUSE NIDA NIAAA National Institute Alcohol Abuse and Alcoholism Nora D. Volkow, M.D. Director, National Institute on Drug Abuse.

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Presentation on theme: "NATIONAL INSTITUTE ON DRUG ABUSE NIDA NIAAA National Institute Alcohol Abuse and Alcoholism Nora D. Volkow, M.D. Director, National Institute on Drug Abuse."— Presentation transcript:

1 NATIONAL INSTITUTE ON DRUG ABUSE NIDA NIAAA National Institute Alcohol Abuse and Alcoholism Nora D. Volkow, M.D. Director, National Institute on Drug Abuse Nora D. Volkow, M.D. Director, National Institute on Drug Abuse Dopamine’s Role in

2 Dopamine Neurotransmission VTA/SN nucleus accumbens nucleus accumbens frontal cortex frontal cortex 0 0 100 200 300 400 500 600 700 800 900 1000 1100 0 0 1 1 2 2 3 3 4 4 5 hr Time After Amphetamine % of Basal Release AMPHETAMINE 0 0 50 100 150 200 0 0 60 120 180 Time (min) % of Basal Release Empty Box Feeding Di Chiara et al. FOOD

3 TYROSINE DA DOPA DA DA DA DA TYROSINE DA DOPA DA DA DA DA DA DA DA DA DA DA methylphenida te R R R R R R -10010203040 -2 0 2 4 6 8 10 High (0-10) Change in Dopamine Bmax/kd (Placebo - MP) “High” DA and Drug Reinforcement raclopride DA DA initiates and maintains responses to salient stimuli such as drugs

4 The mechanism(s) underlying the intense desire for the drug when addicted subjects are exposed to drug cues (places, people and paraphernalia linked with the drug), is still unknown. Since DA is involved with reward and with prediction of reward, it could underlie craving The mechanism(s) underlying the intense desire for the drug when addicted subjects are exposed to drug cues (places, people and paraphernalia linked with the drug), is still unknown. Since DA is involved with reward and with prediction of reward, it could underlie craving

5 Background In rodents when a neutral stimuli is repeatedly paired with the drug (conditioned), it elicits DA increases. Philipps et al Nature 422, 614-618 DA Release NAc Auditory cue In training the cue was paired with cocaine In training the cue was not paired with cocaine

6 Eighteen cocaine abusers Inclusion criteria: –DSM- IV criteria for cocaine dependence –active use for at least the prior 6 months – free-base or crack –at least "four grams" a week Exclusion criteria: –past or present neuro and psychiatric diseases other than cocaine dependence –past or present endocrinological disease –head trauma with loss of consciousness –current medical illness Eighteen cocaine abusers Inclusion criteria: –DSM- IV criteria for cocaine dependence –active use for at least the prior 6 months – free-base or crack –at least "four grams" a week Exclusion criteria: –past or present neuro and psychiatric diseases other than cocaine dependence –past or present endocrinological disease –head trauma with loss of consciousness –current medical illness 1. Subjects

7 Methods: Videos The neutral video featured non-repeating segments of nature scenes The cocaine-cue video featured non repeating scenes that simulated purchase, preparation, and smoking of cocaine The neutral video featured non-repeating segments of nature scenes The cocaine-cue video featured non repeating scenes that simulated purchase, preparation, and smoking of cocaine Videos were shown 10 min prior to radiotracer injection for a total of 40 min Videos were shown 10 min prior to radiotracer injection for a total of 40 min

8 Self-reports of craving during the neutral and the cocaine-cue video 2.00 2.50 3.00 3.50 4.00 4.50 5.00 Cocaine Craving P < 0.01 Before After Cocaine cues increased self reports of cocaine craving in cocaine abusers 2.00 2.50 3.00 3.50 4.00 4.50 5.00 Cocaine Craving (1-7) Before After Neutral Video Cocaine-Cue Video Source: Volkow, ND et al., Journal of Neuroscience, 26(24):6583-6588, 2006.

9 Cue-induced increases in DA were associated with craving P < 0.002 % Change Bmax/Kd -0.50 0.0 0.50 1.0 1.5 2.0 2.5 -40 -30 -20 -10 0 0 10 20 30 Putamen -0.50 0.0 0.50 1.0 1.5 2.0 2.5 -40 -30 -20 -10 0 0 10 20 30 Change in Craving (Pre - Post) Caudate Relationship between Cue-Induced Decreases in [11C]raclopride Binding and Cocaine Craving P < 0.05 Source: Volkow, ND et al., Journal of Neuroscience, 26(24):6583-6588, 2006.

10 Craving of Food Why is it that the sight of food can elicit the desire for it even when we are not hungry? Are the responses to cues similar to those that triggered the cocaine in cocaine abusers?

11 Neutral: Subjects were asked to describe their family genealogy. Food Cues: The food-cue featured non repeating presentation of favorite foods that had been heated to enhance smell Neutral: Subjects were asked to describe their family genealogy. Food Cues: The food-cue featured non repeating presentation of favorite foods that had been heated to enhance smell Stimuli were presented 10 min prior to radiotracer injection for a total of 40 min Stimuli were presented 10 min prior to radiotracer injection for a total of 40 min Ten healthy food deprived controls (15-18 hours food deprivation) tested under neutral and food cue conditions

12 Bmax/Kd decreased with exposure to food-cues presumably from DA increases Neutral Food Cue [ 11 C]Raclopride Binding in Food Deprived Controls During Neutral and Food Cues (Bmax/Kd) 2.5 3 3 3.5 4 4 Placebo/Neutral MP/Food p < 0.005 1.5 0 0 ml/g Source: Volkow, et al., Synapse 2002.

13 Relationship Between DA Changes and Self- Reports of Hunger and Desire for Food Induced by Food Cues 051015202530 -2 0 2 4 6 8 10 Hunger -2 0 2 4 6 8 10 05 15202530 Desire for Food % Change Bmax/kd p < 0.01

14 DA activation of DS may underlie the “ desire ” (wanting) that result in the readiness to engage in the behaviors necessary to procure the desired object whether it ’ s a drug or food DA activation of DS may underlie the “ desire ” (wanting) that result in the readiness to engage in the behaviors necessary to procure the desired object whether it ’ s a drug or food Cue-induced DA increases were associated with craving for drugs as well as for food, which highlights the automated (reflexes) nature of these responses Both drug as well as food cues increased DA in dorsal striatum (brain region involved with initiation of action and with learning of habits), suggesting that drugs usurp physiological processes

15 Funded by DOE and NIH F. Telang, R. MacGregor, P. Carter, D. Schlyer, C. Shea, J. Gatley, S. Dewey, C. Redvanly, P. King L. Caligiuri, G-J Wang, M. Franceschi, Y-S Ding, J. Logan, N. Volkow, J. Fowler, R. Ferrieri, C. Wong (not shown) D. Alexoff, C. Felder, N. Pappas, D. Franceschi, N. Netusil, V. Garza, R. Carciello, D. Warner, M. Gerasimov

16 Brain Dopamine Response to Food Stimulation (Bmax/Kd) 2.5 3 3 3.5 4 4 Placebo/Neutral MP/Food p < 0.005 1.5 0 0 ml/g Source: Volkow, et al., Synapse 2002. -2 0 0 2 2 4 4 6 6 8 8 10 0 0 5 5 15 20 25 30 Desire for Food % Change Bmax/kd p < 0.01 Neutral Food

17 Gender 17 males, 1 female Age 43  6 years Ethnicity 15 AA, 3 Caucasians Education 13  2 years of education Years used 15  7 years Route 18 smoked cocaine Dose used 2.8  1.6 grams a day Last used 2  1.4 days (range 1 & 6 days) Cigarette smokers 15 current smokers Gender 17 males, 1 female Age 43  6 years Ethnicity 15 AA, 3 Caucasians Education 13  2 years of education Years used 15  7 years Route 18 smoked cocaine Dose used 2.8  1.6 grams a day Last used 2  1.4 days (range 1 & 6 days) Cigarette smokers 15 current smokers 2. Subjects


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