Caffeine and Adenosine Mechanisms Flashcards
What natural function does caffeine serve in plants?
It acts as a pesticide.
What molecule builds up in the brain during the day and promotes sleep pressure?
Adenosine (A)
What kind of receptor does adenosine bind to?
A2A adenosine receptor
What effect does adenosine binding to A2A receptors have on neurons?
It produces IPSPs (inhibitory postsynaptic potentials), reducing activity.
How does caffeine promote alertness?
It blocks adenosine from binding to A2A receptors, preventing IPSPs.
What kind of drug is caffeine in terms of adenosine receptor action?
Adenosine antagonist
Does caffeine directly stimulate dopamine receptors?
No, it indirectly increases dopamine activity by blocking adenosine’s inhibition.
What effect does adenosine normally have on dopamine receptors?
It reduces their effectiveness.
By blocking A2A receptors, what happens to dopamine signaling?
It becomes more effective (DA activity increases).
What other neurotransmitters does adenosine antagonize?
Norepinephrine (NE), acetylcholine (ACh), and glutamate.
What cognitive benefits result from caffeine blocking adenosine’s effects on ACh and glutamate?
Improved learning and memory.
What happens to sleep pressure when caffeine is consumed?
It is reduced due to less adenosine receptor activation.
How does adenosine accumulation normally affect cerebral cortex neurons during the day?
It increases IPSPs, reducing neuronal firing and energy.
How does caffeine cross into the brain?
It crosses the blood-brain barrier (BBB).
