To date, little to no information can be found on gender-related differences in BBB permeability. Gender is an important variable that may contribute to differences in pharmacokinetics (PK) including uptake, absorption, distribution, metabolism, and excretion of drugs. Investigating the role of AR signaling in modulation of the BBB has direct relevance to key areas of male and female physiology. These include improving the outcome of hormone replacement in men and women, efficiency in drug delivery across the BBB for treatment of neurological diseases, ranging from Alzheimer’s to brain tumors, and reduction in potential toxicity due to inadequate dosing/PK. These studies will the first critical steps in addressing this important area of study. It would provide preliminary data for future studies investigating gender differences in BBB regulation. If time and funding permits, we would perform proteomic and/or gene analysis studies that may provide molecular targets for future investigation.