You will be given a definition of a task first, then some input of the task.
Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.

Question: Is the clinical antidepressant effect of exogenous agmatine reversed by parachlorophenylalanine : a pilot study?
Answer: The antidepressant effect of exogenous agmatine was documented in a small number of MDD subjects, and was not reversed/modified by PCPA confirming findings in animals that therapeutic response is not mediated by serotonergic mechanisms. A NAMDA (N-methyl-D-aspartate) receptor antagonist, agmatine's recognized function in brain as inhibitory modulator of excitatory glutamatergic transmission suggests a pivotal role for brain glutamate, contributing to the ripening glutamatergic basis of depression, and a rational basis for future antidepressant pharmacotherapy.
Output:
no