The Choroid Plexus Is an Alternative Source of Prolactin to the Rat Brain.
Blood-cerebrospinal fluid barrier
Brain
Choroid plexus
Prolactin
Prolactin receptor
Journal
Molecular neurobiology
ISSN: 1559-1182
Titre abrégé: Mol Neurobiol
Pays: United States
ID NLM: 8900963
Informations de publication
Date de publication:
Apr 2021
Apr 2021
Historique:
received:
06
07
2020
accepted:
16
12
2020
pubmed:
8
1
2021
medline:
28
10
2021
entrez:
7
1
2021
Statut:
ppublish
Résumé
Among the more than 300 functions attributed to prolactin (PRL), this hormone has been associated with the induction of neurogenesis and differentiation of olfactory neurons especially during pregnancy, which are essential for maternal behavior. Despite the original hypothesis that PRL enters the central nervous system through a process mediated by PRL receptors (PRLR) at the choroid plexus (CP), recent data suggested that PRL transport into the brain is independent of its receptors. Based on transcriptomic data suggesting that PRL could be expressed in the CP, this work aimed to confirm PRL synthesis and secretion by CP epithelial cells (CPEC). The secretion of PRL and the distribution of PRLR in CPEC were further characterized using an in vitro model of the rat blood-cerebrospinal fluid barrier. RT-PCR analysis of PRL transcripts showed its presence in pregnant rat CP, in CPEC, and in the rat immortalized CP cell line, Z310. These observations were reinforced by immunocytochemistry staining of PRL in CPEC and Z310 cell cytoplasm. A 63-kDa immunoreactive PRL protein was detected by Western blot in CP protein extracts as well as in culture medium incubated with rat pituitary and samples of rat cerebrospinal fluid and serum. Positive immunocytochemistry staining of PRLR was present throughout the CPEC cytoplasm and in the apical and basal membrane of these cells. Altogether, our evidences suggest that CP is an alternative source of PRL to the brain, which might impact neurogenesis of olfactory neurons at the subventricular zone, given its proximity to the CP.
Identifiants
pubmed: 33409838
doi: 10.1007/s12035-020-02267-9
pii: 10.1007/s12035-020-02267-9
doi:
Substances chimiques
Peptides
0
RNA, Messenger
0
Receptors, Prolactin
0
Prolactin
9002-62-4
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
1846-1858Subventions
Organisme : Fundação para a Ciência e a Tecnologia
ID : UID/Multi/00709/2013
Organisme : Fundação para a Ciência e a Tecnologia
ID : UID/Multi/00709/2019
Organisme : Fundação para a Ciência e a Tecnologia
ID : SFRH/BD/121890/2016
Organisme : Sociedade Portuguesa de Endocrinologia Metabolismo e Diabetes
ID : "Sociedade Portuguesa de Endocrinologia Diabetes e Metabolismo/Novartis Oncology em Patologia Hipofisária 2019"
Organisme : Programa Operacional do Centro, Centro 2020 - Interdisciplinary Challanges On Neurodegeneration, ICON
ID : CENTRO-01-0145-FEDER-000013
Organisme : PPBI - Portuguese Platform of BioImaging
ID : POCI-01-0145-FEDER-022122
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