Expression of aquaporin-7 and aquaporin-9 in tanycyte cells and choroid plexus during mouse estrus cycle

Morphologie. 2017 Mar;101(332):39-46. doi: 10.1016/j.morpho.2016.09.001. Epub 2016 Oct 13.

Abstract

Tanycytes are special ependymal cells located in the ventrolateral wall and floor of the third ventricle having processes extending nuclei that regulate reproductive functions and around of vessels in median eminance. The aquaporins (AQPs) are a family of transmembrane proteins that transport water and glycerol. AQP-7 and -9 are permeable to other small molecules as glycerol and therefore called aquaglyceroporins. In this study, we aimed to show localization of AQP-7 and -9 in epithelial cells of choroid plexus and tanycytes during female mouse estrus cycle. AQP-7 and -9 proteins were detected in α2 and β1 tanycytes in prœstrus stage. Interestingly, there is no staining in estrus stage in any type of tanycytes. We observed weak immunoreactivity in α1, α2 and β1 tanycyte cells in metestrus stage for AQP-7 and α1 for AQP-9 protein. AQP-7 and -9 showed intense immunoreactivity in α2, β1 and β2 tanycyte cells during diestrus stage. Consequently, AQP-7 and -9 showed differential staining pattern in different stages of mouse estrus cycle. In the light of our findings and other recent publications, we suggest that AQP-7 and -9-mediated glycerol transport in tanycyte cells might be under hormonal control to use glycerol as a potential energy substrate during mouse estrus cycle.

Keywords: AQP-7; AQP-9; Cycle œstral; Estrus cycle; Mouse; Souris; Tanycyte; Tanycyte cells.

MeSH terms

  • Animals
  • Aquaporins / metabolism*
  • Biological Transport
  • Choroid Plexus / cytology
  • Choroid Plexus / metabolism*
  • Ependymoglial Cells / metabolism*
  • Epithelial Cells / metabolism
  • Estrous Cycle / metabolism*
  • Estrus / metabolism
  • Female
  • Glycerol / metabolism
  • Metestrus / metabolism
  • Mice
  • Mice, Inbred BALB C
  • Proestrus / metabolism
  • Third Ventricle / cytology

Substances

  • Aqp7 protein, mouse
  • Aqp9 protein, mouse
  • Aquaporins
  • Glycerol