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: Physiology
[{'content': 'Which of the following represent the mechanism of action of Memantine? \nSelect and explain. \nA. GABA antagonist, B. Alpha 2 antagonist, C. 5HT 2A antagonist, D. NMDA antagonist', 'role': 'user'}, {'content': "Answer: D \nExplanation: Memantine works as a NMDA receptor antagonist. It is used to slow the progressive decline in patients with Alzheimer disease. Other commonly used NMDA receptor antagonists are: Riluzole which is used to slow the progression of impairment and modestly improve the life expectancy of patients with amyotropic lateral sclerosis. Amantadine is used along with levodopa to improve function in patients with Parkinson disease. Ref: Barrett K.E., Barman S.M., Boitano S., Brooks H.L. (2012). Chapter 7. Neurotransmitters & Neuromodulators. In K.E. Barrett, S.M. Barman, S. Boitano, H.L. Brooks (Eds), Ganong's Review of Medical Physiology, 24e.", 'role': 'assistant'}]