It is intended to provide a method for studying, determining or evaluating a pharmacological effect such as an effect on fibromyalgia, an analgesic effect or an antistress effect of a test substance by administering the test substance to a SART stress-loaded animal and then subjecting the brain tissue to expression and proteome analysis. By conducting the expression and proteome analysis to examine how the test substance affects a change in protein expression occurring in the brain tissue of the SART stress-loaded animal, it is possible to search for a substance efficacious against fibromyalgia or painful diseases, an antistress agent and so on.