Despite having been object of a considerable amount of researchin the past, scientists continue finding out more about howcaffeine
Andrew Watt, PhD candidate from the University of Melbourne,started a new
Caffeine – “A block of wood under a brakepedal”
“Enter caffeine. Whether from your coffee, your tea, yourchocolate or your guarana, it flows into your body, headingstraight for your adenosine receptors, or more specifically youradenylyl cyclase-modulating g protein-coupled A1 receptors. Once atthe receptor it binds with great efficiency, due to itssimilarities with adenosine. However its differences mean thatdespite binding, caffeine doesn’t actually activate the receptorand so no sleep signal is sent to the brain. So with caffeineacting like “a block of wood under one of the brain’s primary brakepedals”, the brain’s natural stimulants, dopamine and glutamate,are left to do what they do best.
Of course we each have differing amounts of these naturalstimulants floating around our heads at any given moment and so theeffect of a coffee is somewhat variable from person to person andat different times of the day. The take home message is that coffeedoesn’t act to wake you up, but rather it acts to stop you fromgoing to sleep. Which isn’t quite the same thing, when you reallythink about it.”