De Sousa SMC, et al. – The physicians conducted this work to determine whether the observed hyperprolactinemia is due to a vascular–derived or known prolactin secretagogue from the injured internal carotid artery (ICA), analogous to pregnancy–associated hyperprolactinemia putatively due to placental factors. They offer the term ‘vasculogenic hyperprolactinemia’ to encompass the hyperprolactinemia correlated with ICA aneurysms. Moreover, this may be mediated by an endothelial factor capable of paracrine stimulation of lactotrophs; nevertheless, angiotensin II, substance P, histamine and PRLH appear unlikely to be causative.