Psychoactive drugs Flashcards
what are the ways to use meth
smoking - most common, easiest, fastest
ingestion
snorting
injection - fastest
what are the short term effects of meth use
- increased wakefulness and PA
- increased BP and HR
- appetite suppression
- increased body temp
- high risk sexual behaviour
what are the long term symptoms of meth use
- paranoia, anxiety, confusion, hallucinations
- itching, picking skin sores
- dental problems
- memory loss
- sleeping problems
- violent behaviour
- permanent brain structure changes
what does meth use cause
increased synaptic concentration of dopamine, norepinephrine, and serotonin
what are the methods of action of meth
- meth binds to TAAR1 (trace amine associated receptor 1) when they enter
- inhibiton of DAT (dopamine active transporter)
— normal job is to remove dopamine from the synapse and put it back in the nerve (doesn’t happen) - increased calcium in cytosol (inside axon) = exocytosis of dopamine
- overall dopamine efflux (more dopamine out into synapse than in)
what are the meth withdrawal symptoms
fatigue, severe depression, psychosis, drug cravings
decreased sensitivity to dopamine
- inability to feel pleasure
- requires intense stimulation of dopamine pathways to have regular functioning
what are the effects of norepinephrine
released during meth use
- both an NT and a hormone (active on neurons and other tissues in the body)
- activates the sympathetic NS
what is the change in dopamine scaling of reward during higher doses of meth
higher doses of meth = higher reward = more likely to get addicted
what is the difference when using faster releasing methods of meth ingestion (temporal discounting)
more dopamine released
more rewarding behaviour = injecting/smoking = more likely to addicted
what is believed to be the cause of ADHD
lack of norepi and dopamine
what are the differences between brain volume in ADHD vs non ADHD children
ADHD children have smaller brain volume (less prominent in adults)
- lower volume in accumbens, caudate, putamen (all part of reward pathway), amygdala (emotional regulation), and hippocampus (memory retention)
what are the differences in brain function between ADHD and non ADHD children
- decreased blood flow to prefrontal areas (logical decision making decreased)
- slowed brain maturation, brain never reaches full maturation in adulthood
- dopamine dysregulation
— low dopamine
— low dopamine sensitivity (less receptors on neurons)
— low efficiency (not reuptaken and loaded properly)
what do SSRIs do
increases amount of serotonin in the synapse
acts more on NTs
what are the downsides of SSRIs
lots of side effects
includes:
suicidal ideation, sexual dysfunction, serotonin syndrome, osteoporosis
what is serotonin’s function
most serotonin is found outside the CNS
some action on the regulation of almost all human behaviour
- low levels of serotonin linked to depression
what is the connection between serotonin and the gut
95% of total body serotonin is released into the gut
- activation of taste buds on the tongue cause serotonin release onto sensory afferent nerves to the CNS
- peristalsis is modulated by serotonin as food enters the gut
- also regulates pancreatic enzyme secretion
what is glyphosate (roundup)
neurotoxin
linked to anxiety, depression, IBS, ASD, cancer, liver/kidney damage
what are NDRIs
antidepressants
- little to no effect on serotonin (less side effects)
- sometimes used to treat ADHD or chronic pain
- increases sympathetic NS activity
what are alternative depression treatments
exercise - no difference to SSRIs
1000 mg of EPA omega 3s - similar effect as SSRIs
sun exposure - SAD (drop in serotonin due to low vit D)
CBT
changes in diet, probiotics, social support
what does alcohol do
increased release of dopamine in nucleus accumbens
- reward motivation
- inhibits glutamate NDMA receptors
— effect on plasticity, inhibit ability to transfer and store memories
- reduced CRF (corticotropic releasing factor)
what receptor is alcohol an agonist for
GABAAr
what is the difference in GABA with short term vs long term alcohol use
short term
- increased GABA (from body production and alcohol)
long term
- body creates more glutamate and decreases GABA to reach equilbrium so if alcohol use is stopped, GABA is no longer increased from alcohol
what is the difference in CRF with short term vs long term alcohol use
short term
- reduced amount
long term
- increased amount - low reward centre activity
what is GHB - gamma hydroxybutric acid
used in treatment of narcolepsy
- date rape drug
often abused by bodybuilders, fitness industry, rave/EDM
- clear, colourless, salty
what receptor is GHB an agonist for
GABABr
- closes calcium
