title: Pattern of expression of vascular endothelial growth factor and its receptors in the ovine choroid plexus during long and short photoperiods.
abstract: Vascular endothelial growth factor (VEGF-A) plays an important role in maintaining cerebrospinal fluid (CSF) homeostasis and the function of the choroid plexuses (CPs). The objective of the study was to determine the expression of vascular endothelial growth factor (VEGF-A), tyrosine kinase receptors Flt-1 and KDR and KDR co-receptor neuropilin 1 (NRP-1) in ovine CPs during different photoperiods. CPs were collected from the lateral brain ventricles from ovariectomized, estradiol-treated ewes during long day (LD; 16L:8D, n = 5) and short day (SD; 8L:16D, n = 5) photoperiods. We analyzed mRNA expression levels of two VEGF-A isoforms, VEGF-A (120) and VEGF-A (164) and our results indicate that VEGF-A (164) was the predominant isoform. Expression levels of VEGF-A and Flt-1 were similar during the SD and LD photoperiods. There were significant increases in KDR mRNA and protein expression (p < 0.05) and NRP-1 mRNA expression (p < 0.05) during SD. These data show that expression of KDR and its co-receptor NRP-1 are up-regulated by short photoperiod and that this effect is not dependent on ovarian steroids. Our results suggest that the VEGF-A-system may be involved in photoperiodic plasticity of CP capillaries and may therefore be responsible for photoperiodic changes in the CSF turnover rate in ewes.
authors.affiliation: Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Szczepkowska
authors.forename: Barbara
authors.initials: B
authors.lastname: Wąsowska
authors.forename: Przemysław D
authors.initials: PD
authors.lastname: Gilun
authors.forename: Christine
authors.initials: C
authors.lastname: Lagaraine
authors.forename: Vincent
authors.initials: V
authors.lastname: Robert
authors.forename: Laurence
authors.initials: L
authors.lastname: Dufourny
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Thiéry
authors.forename: Janina
authors.initials: J
authors.lastname: Skipor
mesh_terms: D000818:Animals; D000918:Antibody Specificity / Q000276:immunology; D015153:Blotting, Western; D002831:Choroid Plexus / Q000166:cytology / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D017440:Photoperiod; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D055503:Protein Multimerization; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D040262:Receptors, Vascular Endothelial Growth Factor / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D034561:Sheep, Domestic / Q000378:metabolism*; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*
chemical_list: D020033:Protein Isoforms; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D040262:Receptors, Vascular Endothelial Growth Factor