Abstract
Purpose: :
The function of pericyte contraction and its role in blood flow regulation is based on contraction experiments in cell culture and on isolated microvessels. In vivo, due to a lack of appropriate models and technical limitations, the contribution of pericytes to local blood flow regulation has not been proven yet.Retinal and choroidal flat mount preparations of the doublecortin-promoter-dsRed transgenic rat (DCX-dsRed) unveiled dsRed positive cells with perivascular localization. The aim of the present study was to characterize these cells and to analyse whether the DCX-dsRed rat model will be suitable to study pericyte function in vivo.
Methods: :
Eyes from DCX-dsRed rats were analyzed for pericyte, endothelial and neuronal markers using immunohistochemistry and confocal laserscanning microscopy. Whole mounts and sections were tested for the potential pericyte markers NG2, PDGFRb, CD146, as well as CD31 (endothelial marker) and compared with cells positive for DCX-dsRed.
Results: :
In the retina, perivascular dsRed positive cells did not co-localize with NG2, PDGFRb, CD146, and CD31. In the choroid dsRed positive perivascular cells protrude their processes around the vessels and co-localize with the aforementioned pericyte markers.These dsRed positive cells, however, represent a subgroup of the NG2, PDGFRb and CD146 immunreactive cells since perivascular structures were detectable with the pericyte markers lacking the dsRed positive signal.
Conclusions: :
While retinal dsRed positive perivascular cells in the DCX-dsRed rat do not represent pericytes, this is the case in the choroid, since here a co-localization with the pericyte markers NG2, PDGFRb and CD146 was obvious.Although these choroidal dsRed positive cells do not represent the entity of choroidal pericytes, they may be used for further studies on pericyte function and blood flow in vivo.
Keywords: immunohistochemistry • choroid • anatomy