FIBROBLAST GROWTH-FACTORS ALTER LIGHT RESPONSES AND DARK VOLTAGE IN RETINAL RODS OF THE FROG (RANA-TEMPORARIA)

Citation
Kf. Schmidt et al., FIBROBLAST GROWTH-FACTORS ALTER LIGHT RESPONSES AND DARK VOLTAGE IN RETINAL RODS OF THE FROG (RANA-TEMPORARIA), Neuroscience letters, 191(3), 1995, pp. 177-180
Citations number
20
Categorie Soggetti
Neurosciences
Journal title
ISSN journal
03043940
Volume
191
Issue
3
Year of publication
1995
Pages
177 - 180
Database
ISI
SICI code
0304-3940(1995)191:3<177:FGALRA>2.0.ZU;2-O
Abstract
Fibroblast growth factors (FGF-1 and FGF-2) were applied intracellular ly via whole-cell patch-clamp electrodes while the membrane voltage wa s recorded simultaneously. During recording the exchange of substances by diffusion between cytosol and pipette medium affects the cell's fu nction. Under control conditions, the loss of nucleotides is reflected by a slow hyperpolarization of the dark voltage and prolongated light responses. Addition of FGF-1 and FGF-2 to the pipette medium accelera ted the time course of the hyperpolarization and intensified the prolo ngation of the light responses. The depolarization of photoreceptor ce lls after intracellular application of the nitric oxide (NO)-synthase cofactor nicotinamide adenine dinucleotide phosphate (NADPH) and the s tabilization of light response recovery by L-arginine is abolished by FGF-2. FGF-2 was ineffective when it was applied together with the cal cium chelator ethylene glycol-bis(2-aminoethylether)tetraacetate (EGTA ). The results indicate a possible role of FGF in the regulation of NO and calcium in photoreceptor cells and may explain protective effects of FGF in degenerative processes of photoreceptor cells.