Many thanks Harshvardhan

In postmortem human brains dopamine and serotonin do not change for many hours, and can be measured by any of the methods used for animal brain. For living human brains there is no method to measure the content of dopamine and serotonin in the brain. However, it is possible to measure dopamine release using positron emission tomography to look at the displacement of a ligand from dopamine receptors. An example is Biological Psychiatry 2001, 49, 81–96. For serotonin there is a positron emission tomography method that can measure the rate of serotonin synthesis in human brain, PNAS, 1997, 94, 5308-5313.

Regards,

Simon Young

Thank you Simon yes I suspected PET was only available method in vivo. Your input is much appreciated.