<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>Pituitary hormones are produced by the pituitary gland, the master gland of the endocrine system which is located at the base of the brain. Levels of pituitary hormones are regulated by the hypothalamus, anterior and posterior lobes of the pituitary gland, and by the pars intermedia.</n0:def-definition><n0:def-source>NCI</n0:def-source></n0:ComplexDefinition>