Endothelin-1 distribution and basolateral secretion in the retinal pigment epithelium.
Endothelins are a family of conserved vasoactive peptides that are widely expressed in different biological systems including the eye. In the cell culture model of retinal pigment epithelium, ARPE-19, the synthesis and secretion of endothelin-1 (ET-1) is regulated by cholinergics and TNF-alpha. In the present study we investigated the expression of ET-1 in RPE in situ, in rat and human eyes. Additionally, we have employed the human retinal pigment epithelial (ARPE-19) cells to delineate the apical and basolateral ET-1 expression and secretion by confocal microscopy and radioimmunoassay, respectively. Our results suggest a possible conservation of ET-1 expression predominantly in the mammalian RPE underlining its importance at this site. Additionally, our results suggest that constitutive ET-1 secretion is predominantly towards the basolateral side in cultured RPE possibly allowing ET-1 to activate its receptors located in the choroidal blood vessels and regulate retinal and choroidal blood flow.
Narayan
Santosh
S
Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
Brun
Anne Marie
AM
Yorio
Thomas
T
D000818:Animals; D002478:Cells, Cultured; D002829:Choroid / Q000098:blood supply; D019332:Endothelin-1 / Q000032:analysis* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D018613:Microscopy, Confocal; D016253:Microscopy, Immunoelectron; D010857:Pigment Epithelium of Eye / Q000737:chemistry* / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D011914:Rats, Inbred BN; D011921:Rats, Inbred WKY; D012171:Retinal Vessels
D019332:Endothelin-1