Question

binding of epinephrine to its receptor sends a message into the cells and stimulates the second messenger cAMP. once the fight or flight response is no longer needed, cAMP is broken down by the enzyme phosphodiesterase. caffeine blocks the enzyme phosphodiesterase. explain why caffeine produces an energetic feeling

Answer 1

The Epinephrine or the Adrenaline hormone is secreted by the adrenal medulla.The epinephrine hormone is responsible for producing fight or flight response in the individuals,by increasing the heart rate and also increases the blood glucose level by breaking down the stored glycogen in the tissue by the glycogen process.The free glucose enters the cell increases the cellular metabolism,so the cell gets the energy.

So if the cAMP is not activated or degraded by PDE (Phospho Di Esterase) the PKA (Protein Kinase A) the process of Glycolysis is not also initiated so that the glucose level in the blood also does not increases.As a result the cell also does not get enough glucose the metabolism also does not increase and it feels less energetic.

But in case if the Caffeine is present the caffeine blocks the PDE (Phospho diesterase) it can not degrade the cAMP and as a result the PKA is in active state and the Glycolysis is also goes on and as a result it releases free glucose and which in turn increases the cellular metabolism.So Caffeine produces an energetic feeling.