We have found evidence for cyclic adenosine monophosphate (cAMP) response element (CRE) in the 5'-upstream region of the human 14.3.3 eta chain gene during studies on isolation and structure of animal brain 14.3.3 cDNA and the human 14.3.3 eta chain gene. cAMP response element-binding protein (CREB) and phosphorylated CREB (pCREB) may bind to this CRE. Since it was considered that these CREBs may play an important role in molecular mechanisms in the brain of animals treated with methamphetamine, we examined the express of CREB and pCREB in rat brain after acute and chronic methamphetamine administrations using antibodies against CREB and pCREB. We observed findings for change in the expression of these factors. Our findings should be discussed in relation to the data of other authors.