If caffeine blocks the receptors for Adenison, which is responsible for feeling tired/exhausted, why does caffeine help me feel awake in the morning?

Question

After waking up my adenosine level should be very low and l slowly build up upon the day. So why does my morning coffee make me feel awake if there is no adenison to block?

In: 25

Answer 1

You are very much on the right track already. Adenosine can be thought of as a metabolic product that builds up over the day as a result of your brain’s normal functioning. ***But there is always some around***. As you correctly suggest, binding of Adenosine to Adenosine receptors is in part responsible for feeling tired and sleepy. Caffeine can bind to the adenosine receptor first (without actually activating it – like putting glue in a keyhole), and it prevents adenosine from binding, which prevents you from experiencing those signals of feeling tired.Further, sometimes, an antagonist like caffeine can remove adenosine ***already bound to a receptor*** as well. This effect can promote wakefulness by terminating adenosine’s suppressing effects quickly.

Answer 2

You are very much on the right track already. Adenosine can be thought of as a metabolic product that builds up over the day as a result of your brain’s normal functioning. ***But there is always some around***. As you correctly suggest, binding of Adenosine to Adenosine receptors is in part responsible for feeling tired and sleepy. Caffeine can bind to the adenosine receptor first (without actually activating it – like putting glue in a keyhole), and it prevents adenosine from binding, which prevents you from experiencing those signals of feeling tired.Further, sometimes, an antagonist like caffeine can remove adenosine ***already bound to a receptor*** as well. This effect can promote wakefulness by terminating adenosine’s suppressing effects quickly.