The long term goals of our laboratory are to study the transport properties of the blood retinal barrier (BRB) under both normal and pathological conditions. The proposed research represents an extension of our work on glucose transport across the BRB and the initiation of studies into amino acid transport. Since the pigment epithelium (PE) constitutes a major component of the BRB, much of our work is focused on this tissue. Previous work has suggested that two carrier mediated sugar transport systems are in operation at the level of the PE - one of which is phloretin sensitive. We will attempt to determine if these apparently different transport systems are preferentially distributed on the apical and basal sides of the pigment epithelium. The extension of the glucose transport studies will utilize bovine PE tissue mounted as a membrane in a chamber. Studies on amino acid transport across the PE will be initiated to determine the unidirectional flux for representatives of the neutral, basic and acidic groups of amino acids. In addition, ionic dependence and the effects of metabolic inhibitors on amino acid transport will be investigated. Competition studies for common transport sites among amino acids will also be performed. The amino acid transport studies across the PE will also employ the bovine PE tissue mounted as a membrane in a chamber. Information on the transport properties of the BRB is vital to our understanding of such pathological conditions as diabetic retinopathy where an increased permeability of the BRB is the earliest ocular defect noted.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY004750-03
Application #
3259216
Study Section
Visual Sciences A Study Section (VISA)
Project Start
1983-07-01
Project End
1987-06-30
Budget Start
1985-07-01
Budget End
1987-06-30
Support Year
3
Fiscal Year
1985
Total Cost
Indirect Cost
Name
Colorado State University-Fort Collins
Department
Type
Schools of Veterinary Medicine
DUNS #
112617480
City
Fort Collins
State
CO
Country
United States
Zip Code
80523
Pautler, E L; Tengerdy, C; Beyer, J et al. (1989) Modification of leucine transport across bovine pigment epithelium by metabolic stress. Am J Physiol 257:C940-7
Pautler, E L; Hall, F L (1987) Movement of melatonin across the retinal pigment epithelium. Exp Eye Res 45:351-5
Pautler, E L; Maga, J A; Tengerdy, C (1986) A pharmacologically potent natural product in the bovine retina. Exp Eye Res 42:285-8
Pautler, E L; Tengerdy, C (1986) Transport of acidic amino acids by the bovine pigment epithelium. Exp Eye Res 43:207-14
Hall, F; Tengerdy, C; Morita, M et al. (1985) Determination of bovine retinal melatonin with HPLC-EC. Curr Eye Res 4:847-50