PRL In CNS
The PRL in CNS comes from local synthesis and transport from the blood circulation. Besides, the presence of PRL receptors has been identified in different brain regions, such as choroid plexus, olfactory bulb, and hypothalamus [54]. Since 1980s, studies have suggested the relationship between PRL and CNS tumors. Ciccarelli et al reported in 2001 that high PRL levels and increased PRL receptors were found in some of the patients with meningiomas and schwannoms, indicating that PRL might be involved in the growth of the two benign intracranial tumors [9]. The later study by Leães et al in 2007 showed that hyperprolactinemia, intracellular PRL and its receptor were common findings in patients with primary CNS tumors such as meningioma, glioblastoma, astrocytoma, and schwannoma, suggesting a positive action of PRL in the tumorigenesis in CNS [10]. A recent study by Mendes et al further investigated the PRL gene expression in primary CNS tumors through PCR and immunohistochemistry (IH).