stimulants and alcohol

cocaine

blocks monoamine receptor reuptake channels and keeps them in the synapse longer, and vasoconstriction

amphetamines

reverse reuptake chnnels, pushing neurotransmitters out

ritalin

blocks monamine neurotransmitter reuptake but with gradual release

caffeine

blocks adenosine receptors which induce sleep and vasodilation

adenosine

builds up during wakefulness and promotes sleepiness

nicotine

stimulates nicotinic acetylcholine receptors which increase adrenaline and dopamine release

2 types of acetylcholine receptors

• Nicotinic Receptors (nAChRs):

  • Ionotropic (fast).

  • Found in neuromuscular junctions and some CNS areas.

• Muscarinic Receptors (mAChRs):

  • Metabotropic (slow, modulatory).

  • Found in the brain and in parasympathetic target organs.

GABA-A agonisf

alcohol as it increases inhiition - relaxation

NMDA receptor antagonist

alcohol which blocks excitatory function - memory loss

NMDA receptors

glutamate recptor whichplays a key role in synaptic plasitiicyt, learning and memory

what do NMDA receptors require depolarisation

depolarisation of the postsynaptic membraneto remove a magnesium ion blocking the channel to allow ions to flow

why is calcium influx important for memory

through NMDA receptors for long-term potentiation

long-term potentiation

lasting increase in synaptic strength that occurs after repeated stimulation, widely considered a cellular mechanism underlying learning and memory.

reuptake channels

pump neurotansmitters back up to the pre-synaptic terminal to recycle and clear it from the cleft

monoaminergic synapse

primarily uses monoamine receptors to communicate across neurons

monoamine receptors

dopamine, serotonin, norepinephrine, epinephrine

what role do monoamine receptors have

to regulate mood, emotion, arousal and cognition

how do amphetamines help ADHD individuals

they are understimulated therefore need to be active to allow calm

main action of caffeine

blocks adenosine receptors

main action of cocaine

blocks noradrenaline reuptake

effect of caffeine on lateral hypothalamus

keeps it active (prevents inhibition by adenosine)

neurotransmitter involved in caffeine

hypocretine (activates locus coerulus) - orexin

effect of caffeine on locus coerulus

increases activity via hypocretin (orexin) and prevents inhibition by VLPOA

roles of lateral hypothalamus

hunger, arousal, reward and motivation

orexin/ hypocretin

neuropeptide produced in the lateral hypothalamus which promotes wakefulness, increases food intake and reward

deficiency of orexin/ hypocretin

A deficiency in orexin is the main cause of narcolepsy, particularly narcolepsy with cataplexy, a disorder where individuals fall asleep suddenly and may lose muscle control

locus coeruleus

The locus coeruleus is a brainstem nucleus that produces norepinephrine and plays a key role in regulating arousal, attention, stress response, and memory.