2: neurochem effects of alcohol

How long does it take for alcohol to reach the BBB?

It easily enters the brain within mins and changes the lipid bilayer

What are specific alcohol effects

The stimulation or ignition of certain NTs

Non-specific alcohol effects

Alters lipid composition interactions with polar heads of phospholipids, disturbing the relationship of protein the the membrane

What are alcohol’s effects on Glutamate (the major excitatory NT) acute vs chronic

Being an alcohol antagonist, the greatest effect on NMDA receptors and reduces the effect of glutamate by reducing glutamate release (this is acute)

The chronic effect is the up-regulation of NMDA receptors (this is tolerance) in abstinence periods the brain will be more desensitized which will kill neurons due to excessive excitability.

Effect of alcohol on GABA (major inhibitory NT) acute vs chronic

Alcohol will enhance GABA at GABA A receptors, this increases Cl- flux and stimulates GABA release

Acute: enhance GABA, contributes to tolerance to sedative effects

Chronic:reducing GABA induced Cl- influx

Effect of alcohol on dopamine acute vs chronic

NA gets DA input from the VTA and projects to the striatum and frontal cortex (brain’s reward system)

Role of the NA in substance abuse supplies the primary reinforcing qualities Increasing dopaminergic transmission at an acute level

At a chronic level is decrease DA release in the NA