The article discusses a study that was aimed at characterizing neuropeptide Y (NPY) overflow and metabolism from isolated skeletal muscle arterioles of female rats. It cites the use of an isolated microvessel technique to measure this overflow. It stresses a key role being played by dipeptidyl peptidase IV (DPPIV) in regulating the actions of NPY in arterioles of young adult females, based on the results. The impact of age and other vessel characteristics on DPPIV activity is also examined.