Term
| Why are addictive drugs better reinforcers than natural reinforcers? |
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Definition
| They directly activate addictive pathways by chemical means |
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Term
| What features determine the Pharmacokinetics of a particular addictive drug? |
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Definition
Remember, this how the "BODY" handles drugs
RADE
1) Route of administration (IV more rapid)
2) Absorption (Nicotine acidity decreases buccal absorption)
3) Distribution (Heroin passes BBB > morphine)
4) Elimination (CYP2A6 metabollizes nicotine to cotinine) |
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Term
| What is a "partial agonist"? |
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Definition
| High affinity and partial efficacy (think about Chantix for nACR) |
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Term
Match each of the following Receptor systems with the drug that binds them.
1) Endogenous opioid receptor (mu)
2) GABA-A
3) Monoamine receptors (DA, NE, 5-HT)
4) nAChR
5) Adenosine |
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Definition
1) Opioids
2) Benzodiazepines
3) Cocaine
4) Nicotine
5) Caffeine |
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Term
| What are the 2 main types of long-term effects of drug use? |
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Definition
1) Tolerance- diminished response after repeated exposure (shift to right and down on D-R curve)
- Pharmacokinetic- change absorption, distribution, met.
- Pharmacodynamic- change in response of target system (receptor desensitization)
- Behavioral- conditioned tolerance
2) Sensitization- Enhancement of drug effects following repeated administration (shift to left and up on D-R curve) |
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Term
| What are the Pharmacokinetic, Pharmacodynamic and Behavioral mechanisms of drug Tolerance? |
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Definition
1) Pharmacokinetic- change absorption, distribution, metabolism
2) Pharmacodynamic- change in response of target system (receptor desensitization with cigarette smoking)
3) Behavioral- conditioned tolerance |
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Term
Match each of the following withdrawal symptoms with the receptor systems which bind their associated drugs
1) Yawning, sweating, fitful sleep, nausea, vomiting, diarrhea, cramps/spasms
2) Anxiety, irritability, depression, fatigue, sweating, loss of appetite, insomnia, RHR, fever, delirium, death
3) Tension, irritability, headaches, difficulty concentrating, drowsiness, trouble sleeping, increased appetite/weight gain
4) Depressed mood, fatigue, generalized malaise, vivid unpleasant dreams, slowing of activity, increased appetite. |
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Definition
1) Endogenous opioid receptors (Opioids)
2) GABA-A (Benzodiazepines)
3) nAChR (nicotine)
4) Monoamine (NA, 5-HT, DA) (cocaine) |
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Term
| Which neurotransmitter systems in the medial forebrain bundle are responsible for intracranial self-stimulation in animal models of reinforcement in drug addiction? |
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Definition
1) DA (antagonists suppress ICSS)
- Mesolimbic (VTA to NA and Amygdala via MFB)- lesions reduce/block ICSS
- Mesocortical (VTA to cortex)
**low doses of DA INCREASE ICSS, while high doses attenuate it |
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Term
| What are the different sites of action of abused drugs within the Mesolimbic pathway |
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Definition
VTA to NA and amygdala
1) Opiates inhibit VTA GABA interneurons, thereby preventing the "brake system" on DA outputs from VTA
2) Alcohol may inhibit presynaptic GABA release from these same neurons
3) Nicotine excites DA-releasing neurons in the VTA (through nACHR)
4) Stimulants increase DA signaling from VTA neurons to NAc
5) PCP inhibits Glutamatergic excitation from cortex to NAc |
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Term
| What do the OFC and Cingulate gyrus have to do with reward pathways? |
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Definition
Decreases in their activity reflects a loss of inhibitory control over Mesolimbic DA pathways.
Remember, mesocortical projections can modulate the "glutamate brake system," which excites GABA-ergic interneurons in the VTA, which inhibit mesolimbic DA release. |
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Term
| What are the 3 major neuropharmacological interventions available for treating alcohol abuse? |
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Definition
1) Naltrexone
- Opiate antagonist that decreases cravings and dampens reinforcing effects of alcohol by blocking opioid release, which would normally act in the limbic system
2) Disulfiram
- ADH inhibitor that prevents degradation of alcohol in the body, causing buildup of toxic acetaldehyde (violently unpleasant reaction)
3) Acamprosate
- glu/GABA action and enhancement of maintenance, perhaps synergistically with Naltrexone. |
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Term
| Which drug acts as ADH inhibitor to treat alcohol abuse by inducing violently unpleasant reactions following use? |
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Definition
Disulfiram
prevents degradation of alcohol in the body, causing buildup of toxic acetaldehyde |
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Term
| What drugs can be used for opioid dependence? |
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Definition
Serve as replacement for more dangerous agents
1) Methadone maintenance therapy (hotly debated but effective)
2) Buprenorphine |
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Term
Cocaine addicts show deficits in what neural areas related to inhibitory control?
a. Cingulate gyrus
b. Frontal cortex
c. Hypothalamus
d. A+B
e. All of the above |
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Definition
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Term
How does down-regulation of dopamine receptors in the striatum impact the effectiveness of natural rewards?
a. Decrease
b. Increase
c. No change |
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Definition
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Term
How do drugs of abuse affect the threshold of current required for brain stimulation reward?
a. Decrease threshold
b. Increase threshold
c. Do not affect the threshold |
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Definition
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