TY - JOUR
T1 - Expression of aquaporins in the rat ocular tissue
AU - Patil, Rajkumar V.
AU - Saito, Isao
AU - Yang, Xun
AU - Wax, Martin B.
N1 - Funding Information:
Supported by NEI EY10423 (RVP), and Core Grant for Vision Research, NEI EY02687, and Unrestricted grant from Research to Prevent Blindness, Inc. * Corresponding author: Rajkumar V. Patil, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, 660 South Euclid, St. Louis, MO 63110, U.S.A.
PY - 1997/2
Y1 - 1997/2
N2 - The aquaporins (AQPs) are a rapid growing family of water channel proteins found in animals, plants and microorganisms that raise plasma membrane water permeability required for efficient isosmotic fluid transport. Five homologs of aquaporins (AQP1, AQP2, AQP3, AQP4 and AQP5) have been identified from various mammalian tissues; the expression of these aquaporins in ocular tissues was studied. Semiquantitative expression levels of these aquaporins were determined in ciliary body, cornea, lens, retina, iris and choroid using RT-PCR. Expression levels of AQP1 are highest among the known aquaporins in each rat ocular tissue examined. In cornea, AQP1 is expressed approximately three-fold higher than AQP3 and 2.5 fold higher than AQP5. However, the highest intraocular expressions of AQP3 and AQP5 are in the cornea. In the iris, expression levels of AQP1 are approximately 600-700 fold higher than AQP4 and AQP5. In the ciliary body, the expression levels of AQP1 are approximately ten-fold higher than AQP4, the only other aquaporin expressed. In the lens, the major water channel is AQP1 with detectable levels of AQP4 and AQP5 that are approximately 1000-fold lower than AQP1. In choroid, AQP1 is the only water channel expressed. In retina, AQP1 is expressed approximately six-fold higher than AQP4, the only other aquaporin expressed. However, the highest ocular expression of AQP4 is in retina. AQP2 is not detected in the eye. Finally, the possible physiological roles of aquaporins in maintaining and regulating the aqueous flow, and corneal and lens transparency are discussed.
AB - The aquaporins (AQPs) are a rapid growing family of water channel proteins found in animals, plants and microorganisms that raise plasma membrane water permeability required for efficient isosmotic fluid transport. Five homologs of aquaporins (AQP1, AQP2, AQP3, AQP4 and AQP5) have been identified from various mammalian tissues; the expression of these aquaporins in ocular tissues was studied. Semiquantitative expression levels of these aquaporins were determined in ciliary body, cornea, lens, retina, iris and choroid using RT-PCR. Expression levels of AQP1 are highest among the known aquaporins in each rat ocular tissue examined. In cornea, AQP1 is expressed approximately three-fold higher than AQP3 and 2.5 fold higher than AQP5. However, the highest intraocular expressions of AQP3 and AQP5 are in the cornea. In the iris, expression levels of AQP1 are approximately 600-700 fold higher than AQP4 and AQP5. In the ciliary body, the expression levels of AQP1 are approximately ten-fold higher than AQP4, the only other aquaporin expressed. In the lens, the major water channel is AQP1 with detectable levels of AQP4 and AQP5 that are approximately 1000-fold lower than AQP1. In choroid, AQP1 is the only water channel expressed. In retina, AQP1 is expressed approximately six-fold higher than AQP4, the only other aquaporin expressed. However, the highest ocular expression of AQP4 is in retina. AQP2 is not detected in the eye. Finally, the possible physiological roles of aquaporins in maintaining and regulating the aqueous flow, and corneal and lens transparency are discussed.
KW - RT-PCR
KW - aquaporins
KW - mRNA
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U2 - 10.1006/exer.1996.0196
DO - 10.1006/exer.1996.0196
M3 - Article
C2 - 9176054
AN - SCOPUS:0031080640
SN - 0014-4835
VL - 64
SP - 203
EP - 209
JO - Experimental Eye Research
JF - Experimental Eye Research
IS - 2
ER -