Lecture 3: Ethyl Alcohol Flashcards
Alc is the BLANK most used BLANK in the world
second, psychoactive substance
What are some characteristics of alcohol? drink amount and burn-off rate
one drink = 10 cc (1/3 oz) 100% ethanol
Body reduced BAC by 0.015g% in 1hr (rate limiting step)
Types: beer, spirits and bubbly
Soluble in both water and fat - higher absorption in women
BBB and placental barrier are permeable to alc
Where is alc absorbed in the body?
Esophagus
Stomach - 20%
Upper intestines - 80%
Lower intestines
What ezyme is alc metabolized by? where does it occur and in what percentage (2 places)?
What is the max EtOH metabolized in 24hr?
- 95% of alc is metabolized by alc dehydrogenase
- 85% of metabolism occurs in the liver
- 15% by first-pass metabolism - may differ based on stomach contents
170g, or 7-8g of 100% per hr (1 drink per hr)
How does one calculate BAC? what variables are needed?
Consumption and body weight (hours, drinks, body weight)
BAC of 0.08 = intoxicated
What drug can be given to help treat alcoholism?
Acetaldehyde - induces illness when alc is consumed
Why are their gender differences in alc tolerance?
Women have a lower level of gastric al dehydrogenase
Men have a greater ratio of muscle/fat (larger vascular compartment - larger volume of blood to take in alcohol/dilute alc)
Women have higher body fat, this concentrates alc in plasma
Which systems/processes are effected by alc?
glutamate s
gaba s
intaracellular transduction p
What are the pharmacodynamics of GluR?
Inhibits NMDA receptors (lowers excitation) - chronic exposure = up-regulation of NMDAR
Withdrawal can lea to hyperexcitability (2 much NMDA = seizures)
Acamprosate (structurally similar to glutamate)
What are the pharmacodynamics of GABA?
Activates GABAR - results in neuronal inhibition, depressant qualities are chemical, hype is psychological
Binds to specific site on GABAaR - may reduce anxiety and panic, GABA agonistic action linked to positive reinforcing effects of the drug
What is the relevance of opiod/opiod receptors in alc dependence? what can be given to mitigate this?
Alc dependents & offspring show deficit in opioid activity
Subconsciously consuming to increase opioid activity
EtOH induced opioid release, dopamine release
Naltrexone blocks opioid release, reduces craving
What are the pharmacodynamics of 5-HT receptors?
Agonistic action on 5-HT2-3 located on DA neurons in nucleus accumbens (part of dopamine reward pathway), antagonist drugs block these receptors reduce EtOH intake
5-HT transporter dysfunction may be involved
What are the pharmacodynamics of cannabinoid R?
chronic exposure leads to formation of endogenous NT anandamide - which activates cannabinoid receptor = possible down-regulation
Abstinence lead to hyperactive receptor activation, promotes cravings
What are the pharmacological effects of EtOH? what are some positves?
Graded reversible depression of behavior and cognition
Depression of respiration - chronic exposure can stop breathing
Additive effects with other sedative-hypnotic compounds
Reduction in circulatory function, dilates blood vessels
2-3 times a week of a decent wine
- low doses reduce risk of coronary artery disease and stoke
- increases in HD-lipoprotein (good fats) and HD-cholesterol (good chol)
What are the psychological effects of EtOH?
Hint: 3 activation effects
Intoxication associated with violent crimes - fights, rape and sexual assault
Alc is implicated in more than half of all homicides
Activation in GABA system - reduces anxiety
Activation in DA system - impulse control is reduced, increases aggression
Depression of glutamate system - impaired cognitive function, alc myopia, cognitive and attentional deficits
What are the variables affected tolerance and dependence? what are the different types of tolerance (3)?
Amount of ingestion, pattern of consumption, individual differences
Metabolic tolerance, tissue/functional tolerance, homeostatic tolerance (environmental)
What are the side effects and toxicity during acute use? high doses/chronic use?
what are the physical manifestations?
- Clouded sensorium
Impaired judgement
Anterograde amnesia (blackouts - moment of consumption onwards) - Delusions
Hallucinations
Unconscious - Liver damage (cirrhosis)
Dementia (nerve damage)
Wernicke korsakoff’s syndrome (above symptoms and more)
Digestive problems (pancreatitis, chronic gastritis)
Cancer (indirect contributor)
What are some teratogenic agents?
ethyl acl, ionizing radiation, thalidomide, lithium
What are some facts about fetal alc syndrome?
Effects 30-50% of infants born to alc women (3-5 per 1000 births) - irreversible
Threshold is unknown but 3oz of absolute EtOH daily increases risk of FAS significantly
CNS damage and physical deformities
What are the three primary features of FAS?
structural, neurological, functional
low IQ, CNS dysfunction, FAS facial/body features
What are some facts related to alcohol related neurodevelopmental disorder?
Effects are seen in 1 out of 100 live births, lesser degree of damage than FAS = milder symptoms
- hyperactivity, aggressive behavior, sensory problems, low IQ
What are the primary treatments for alc dependency withdrawals? What is best?
Benzos - for acute alc withdrawal, increases GABA activity, remove symptoms (seizures, dts), sedation, psychomotor deficits, interactions with EtOH dependence
Antipsychotics - alleviate DT and hallucinations, lower threshold for seizure, withdrawal seizures
Anticonvulsants - used in place of benzos, fewer side effects, ma contribute to liver/pancreatic problems
(topamax effective in treating alc dependency)
Combination = best
How can you maintain abstinence/prevent relapse? (drugs)
Alc sensitizing drugs - antabuse
Opioid antagonists - naltrexone
Acamprosate - GABA agonist, inhibits GluR
Dopaminergic drugs - wellbutrin (comorbid with depression)
Serotonergic drugs
Resources offered by campuses to prevent alc abuse…
Preventative campaigns
Counseling
Campus regulations
Enforcement
What is the correlate between age and abuse and campus prevelance?
2004 Canadian addiction survey (CCSA)
- YA drink more than people over 25
- students drink more than general population aged 18-24
Early exposure impacts addiction - threshold lies prior to 17 years (25% change of becoming addict, 34% for 13 y/0)
Why are young people more prone to alc addiction?
Differences linked to DA sensitivity - young brains spike faster/more
Adolescent brain may be more sensitive to VTA (Validated in in vitro mouse studies)
How does a breathalyzer indirectly measure BAC? what is the math here?
EtOH transfers from blood to alveolar sacs in the lungs - in an exhale there is BRAC (breath alc concentration)
Can predict BAC from known ratio (BAC 2 BRAC) = .08 over .2
What are the different types of devices to measure BAC?
Breathalyzer: Chemical reaction - color change
Intoxilyzer: infared spectroscopy
Alcosensor III or IV = chemical - fuel cell
What is the composition of a breathalyzer?
breath acquisition - mouthpiece
Chemical substrates - glass vials
Photocells & meter - detection
What is the process of a breathalyzer reaction?
Hint: 4 a agents - 1 is a product
Potassium dichromate - receive agent, changes colour
Sulfuric acid - helps coax alc out of breath
Silver nitrate - catalyst
Product - chromium sulfate
What are some potential sources of error with breathalyzer tests?
What are some breathalyzer myths?
Air temperature
Breathing rate (running lowers (11-14), breath hold bumps up (15) percentage of alc detected
Burping - higher, big expulsion of air that pushes out alc
Disguise odor with food
Chew gum or use mouthwash (experiment suggest mouthwash creates false positives)
