Alcohol Flashcards
What mediates Alcohol’s amnestic effects?
Inhibited NMDA receptor function
NMDA mediates memory and learning
What mediates Alcohol’s euphoric effect?
Increased dopamine release in the nucleus accumbens
What mediates Alcohol’s sedative effects?
Enhanced GABA-A receptor function
Chloride conduction
What mediate’s Alcohol causing coma/death?
Inhibiting voltage-sensitive calcium channels
Fluidizing cell membranes
What blood alc conc leads to the first signs of intoxication?
20 mg%
What blood alc conc leads to being legally impaired in many states?
50 mg%
What blood alc conc makes you 7x more likely to cause an accident?
100 mg%
What blood alc conc makes you 25x more likely to cause an accident?
150 mg%
What blood alc conc is lethal?
400 mg%
One drink per hour will lead to what blood alc conc?
30 mg%
What is the difference between first signs of intoxication and lethal dose?
20 fold difference
STEEP dose response curve
Why do we get easily dehydrated when we drink?
Alcohol inhibits ADH secretion; decreases renal reabsorption of water, we pee more
How is alcohol metabolized?
90-90% hepatic (mostly dehydrogenase, some CYP2E1), the rest is excreted unchanged by the lungs
How is ethanol metabolized in the liver?
Ethanol is metabolized by alcohol dehydrogenase (zero order kinetics) to acetaldehyde, using NADH to NAD+
Acetaldehyde is then metabolized by acetaldehyde dehydrogenase (first order kinetics) to Acetyl CoA, using NADH to NAD+
How does chronic alcohol use affect ethanol metabolism?
Upregulation of alcohol dehydrogenase
Down regulation of acetaldehyde dehydrogenase
How fast is alcohol metabolized?
7-10 g/hr or 14-20 mg%/hr
Avg drink has 14 g ethanol
How can you treat methanol intoxication?
Ethanol or fomepizol
Ethanol will use up the alcohol dehydrogenase
Fomepizol blocks gastric alcohol dehydrogenase
Methanol is metabolized to formic acid - bad!
What drugs inhibit acetaldehyde dehydrogenase?
1st generation oral hypoglycemics, cephalosporins (don’t drink while on these meds!)
Metronidazole may in some sub-populations