Chapter 10, Alcohol Flashcards

Question

How does Alcohol impact the Hypothalamus?

Answer 1

When alcohol reaches this brain area, it can cause increased blood pressure, increased hunger and thirst, decreased body temperature, and a decreased heart rate.

Answer 2

Drinking alcohol interferes with this part of the brain’s ability to maintain the body’s normal temperature. Alcohol can also cause slower breathing and heart rate. If a lot of alcohol is used over a short period of time, it can even cause a person to go into a coma when this part of the brain shuts down.

Answer 3

1. Acute tolerance 2. Metabolic tolerance 3. Pharmacodynamic tolerance 4. Behavioral tolerance 5. Cross-tolerance with other depressants

Answer 4

* Intensity and duration of withdrawal signs depend on the amount and duration of drug taking * Hangovers may be evidence of withdrawal (acute toxicity?) * Hangovers are not completely understood, but the symptoms are generally consistent: Headache, fatigue, upset stomach, thirst, general malaise * Acetaldehyde or acetate accumulation * Reactions to congeners

Answer 5

* Alcohol withdrawal can be very dangerous for chronic, heavy drinkers Acute symptoms occur in the hours since the last dose: * Shaking hands and feet * Sweating * Nausea and vomiting * Diarrhea * Tightness in the chest * Elevated BP; Rapid heartbeat * Irregular heart rhythms * Increased body temperature * Some people experience delirium tremens (DTs) and/or seizures * Medical supervision and/or pharmacological treatment is necessary for these individuals * Withdrawal symptoms tend to decrease within 5-7 days but can last for several weeks

Answer 6

* Alcohol primarily facilitates the action of GABA at the GABAA receptor * Hyperpolarization; Increased inhibition * Repeated exposure to ethanol reduces GABAA-mediated Cl–flux; may contribute to tolerance and withdrawal * Alcohol also impacts metabotropic GABAB receptors * Recall metabotropic receptors have slower, more complex effects * GABAB receptors are located pre-synaptically and postsynaptically, and at both GABAergic and Glutamatergic cells * Alcohol affects glutamate by acting as an antagonist at NMDA receptors * Reduced excitation * Repeated use leads to upregulation of NMDA receptors (pharmacodynamic tolerance) * During withdrawal, glutamate release increases causing CNS hyperexcitability (and sometimes seizures) * During withdrawal, glutamate release increases after approx. 10 hrs. Timing correlated with hyperexcitability and seizures are seen in severe alcohol withdrawal

Answer 7

* Alcohol activates dopaminergic cells in the VTA, causing the release of DA in the NAcc, which is involved in positive reinforcement * In rodents, withdrawal after chronic alcohol use reduces the firing rate of mesolimbic neurons and decreases DA release in the Nacc

Answer 8

* Alcohol administration increases opioid production and release * Chronic administration will reduce the production à dysphoria? * Blocking opioid receptors reduces self-administration in animal models * A person’s baseline levels of endorphins may influence their susceptibility to AUD * Opioids probably play a role in alcohol craving * Naltrexone is an opioid receptor antagonist used in the treatment of alcohol use disorder * Reduces alcohol consumption and craving * Improves abstinence rates, but… results are inconsistent; It is greatly beneficial for some and has limited benefit for others

Answer 9

* GABA usually has an inhibitory effect on DA * GABA signalling is modified by glutamate and opioids * Alcohol inhibits glutamate, stimulates the release of endorphins, and reduces GABA’s inhibitory effects, thus increasing DA release in the VTA/NAcc

Answer 10

* No specific cause has been identified, but there are some factors that lead to increased risk: * Anxiety disorders * Genetics * Age at initiation * Stress * Personality factors * Culture Heavy drinking accelerates brain atrophy * Loss of white matter (connectivity), rather than loss of neurons

Answer 11

1. The first step is detoxification * Medication may be used to control dangerous withdrawal symptoms (e.g., benzodiazepines reduce the likelihood of seizures and can prevent anxiety, insomnia, and muscle spasms) * Detoxification length depends on the severity of AUD, but initial detox is usually 1 week 2. The next step is preventing relapse * One pharmacotherapeutic strategy is to make drinking unpleasant by using disulfiram 3. The next step is preventing relapse * One pharmacotherpeautic strategy is to make drinking unpleasant by using disulfiram * Another strategy is to use an opioid receptor antagonist (naltrexone) to reduce the “high” by blocking endorphin release 4. The next step is preventing relapse * One pharmacotherpeautic strategy is to make drinking unpleasant by using disulfiram * Another strategy is to use an opioid receptor antagonist (naltrexone) to reduce the “high” by blocking endorphin release * Some individuals find individual or group therapy to be helpful in maintaining their abstinence

Answer 12

Alcohol can compete with other drugs for CYP enzymes, leading to reduced metabolism of the drug / greater concentrations of the drug in the blood