This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
Best marker for Electro Convulsive Therapy: 
Select and explain. 
A. CSF 5 HIAA, B. CSF serotonin, C. Brain derived growth factor, D. CSF dopamine
C: Brain derived growth factor
Answer: C: Brain derived growth factor 
Explanation: Ans.C. i.e. Brain-derived growth factorECT increases the levels of Brain-Derived Neurotrophic Factor and this mediates the response to ECT in drug-resistant depressed patients.Mechanism of action:- The ability of the brain to form and reorganize synaptic connections, especially in response to learning or experience or following injury.- Increases levels of Brain-Derived Growth Factor and Vascular Endothelial Growth Factor