Karius Neurophysiology of Drug Addiction Flashcards
Having at least 3 of the following = drug addiction
tolerance, withdrawal, desire, use more than you should, continue despite health issues
Describe the “reward (pleasure) system”and its three parts:
1-Ventral Tegmental Area
2-Nucleus Accumbens
3-Pre-frontal cortex
1- gets inputs, releases DA in NA which leads to pleasure
2-D1 activate direct, D3 inhibit indirect pathways. When active GABA is released to produce pleasure
3-gets input allowing pleasure from NA
Dopamine release effect is?
effect of dopamine release is to decrease GABA release in the prefrontal cortex and allow activity of the reward pathways
VTA–>NA–>prefrontal cortex–>______
pathway to pleasure
Amygdala, Hippocampus–>NA–>prefrontal cortex–>______
pathway to ABSENCE of pleasure
To produce _______
Activate the VTA and inhibit the NAc
pleasure
to inhibit pleasure activate the ____
NAc
Drugs of abuse activate ______
GPCRs
Opiates activate?
Gi GPCR
Cannabis activates?
CB-1 receptor = DA release
Nicotine and ethanol/PCP alter what?
ion channels
Cocaine and Amphetamines work how?
interference with reuptake mechanisms
What does CREB do to produce effects of drugs?
within the NAc dynorphin is produced
what causes desensitization?
increase in dynorphin release from the NAc turns the input from the VTA off, reducing the effect of the drugs
Activation of CREB in the locus ceruleus and periaquaductal grey are responsible for what?
dependence on the drugs.
CREB takes a week to get to normal after absence of the drug
