UPTAKE, PROCESSING AND RELEASE OF RETINOIDS BY CULTURED HUMAN RETINAL-PIGMENT EPITHELIUM

被引:58
作者
FLANNERY, JG
ODAY, W
PFEFFER, BA
HORWITZ, J
BOK, D
机构
[1] NEI, PATHOPHYSIOL SECT, MECH OCULAR DIS LAB, BETHESDA, MD 20892 USA
[2] UNIV CALIF LOS ANGELES, SCH MED, DEPT ANAT & CELL BIOL, LOS ANGELES, CA 90024 USA
关键词
IRBP; retinal pigment epithelium; retinoids; retinol binding protein; tissue culture; visual cycle; vitamin A;
D O I
10.1016/0014-4835(90)90057-2
中图分类号
R77 [眼科学];
学科分类号
100212 ;
摘要
Upon absorption of a photon, the 11-cis retinaldehyde chromophore of rhodopsin is isomerized and reduced to all-trans retinol (vitamin A) in the photoreceptor outer segments, whereupon it leaves the photoreceptors, and moves to the retinal pigment epithelium (RPE). To clarify the function of the RPE in the regeneration of 11-cis retinaldehyde, we delivered all-trans retinol to monolayer cultures of human RPE. During delivery the retinol was associated with its putative natural carrier, interphotoreceptor retinoid binding protein (IRBP). IRBP has been proposed as a carrier protein involved in the exchange of retinoids between the photoreceptors and the retinal pigment epithelium. The retinoid composition of RPE cells and culture medium was analyzed by HPLC following several incubation periods. The RPE monolayer was found to process all-trans retinol into two distinct end-products: all-trans retinyl palmitate, which remained within the RPE monolayer; and 11-cis retinaldehyde which was released into the culture medium. These results demonstrate retinoid isomerase, retinol oxidoreductase and retinyl ester synthetase activity in human RPE cells cultured under the appropriate conditions. They show that IRBP can serve as a carrier of retinol through an aqueous medium to the RPE, and they illustrate that the visual cycle can be studied in vitro. © 1990.
引用
收藏
页码:717 / 728
页数:12
相关论文
共 51 条
[1]   RAPID ISOLATION OF BOVINE INTERPHOTORECEPTOR RETINOL-BINDING PROTEIN [J].
ADLER, AJ ;
EVANS, CD .
BIOCHIMICA ET BIOPHYSICA ACTA, 1983, 761 (03) :217-222
[2]   PROTEINS AND GLYCOPROTEINS OF THE BOVINE INTERPHOTORECEPTOR MATRIX - COMPOSITION AND FRACTIONATION [J].
ADLER, AJ ;
KLUCZNIK, KM .
EXPERIMENTAL EYE RESEARCH, 1982, 34 (03) :423-434
[3]   PROTEINS OF THE BOVINE INTERPHOTORECEPTOR MATRIX - TISSUES OF ORIGIN [J].
ADLER, AJ ;
SEVERIN, KM .
EXPERIMENTAL EYE RESEARCH, 1981, 32 (06) :755-769
[4]   RETINOL-BINDING PROTEINS IN BOVINE INTERPHOTORECEPTOR MATRIX [J].
ADLER, AJ ;
MARTIN, KJ .
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 1982, 108 (04) :1601-1608
[5]  
ADLER AJ, 1985, J BIOL CHEM, V260, P4850
[6]   ISOMERIZATION OF ALL-TRANS-RETINOIDS TO 11-CIS-RETINOIDS INVITRO [J].
BERNSTEIN, PS ;
LAW, WC ;
RANDO, RR .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1987, 84 (07) :1849-1853
[7]  
BLANER WS, 1987, J BIOL CHEM, V262, P53
[8]   TRANSPORT OF RETINOL FROM BLOOD TO RETINA - AUTORADIOGRAPHIC STUDY OF PIGMENT EPITHELIAL-CELL SURFACE RECEPTOR FOR PLASMA RETINOL-BINDING PROTEIN [J].
BOK, D ;
HELLER, J .
EXPERIMENTAL EYE RESEARCH, 1976, 22 (05) :395-402
[9]   VITAMIN-A AND ROLE OF PIGMENT EPITHELIUM DURING BLEACHING AND REGENERATION OF RHODOPSIN IN FROG EYE [J].
BRIDGES, CDB .
EXPERIMENTAL EYE RESEARCH, 1976, 22 (05) :435-455
[10]  
BRIDGES CDB, 1984, RETINOIDS, P126