Light-activation of the Phosphoinositide Cycle in Intrinsically Photosensitive Chicken Retinal Ganglion Cells

MARIA A CONTIN; DANIELA M VERRA; GABRIELA SALVADOR; MONICA ILINCHETA; NORMA M GIUSTO; MARIO E GUIDO

ASSOC RESEARCH VISION OPHTHALMOLOGY INC

Lugar: Rockville, MD ; Año: 2010 vol. 51 p. 5491 - 5491

p>Abstract Purpose: In vertebrates, intrinsically photosensitive retinal ganglion cells (ipRGCs) acting as non-visual photoreceptors transmit environmental illumination information to the brain, regulating diverse non-image-forming tasks. We have demonstrated that the phototransduction cascade occurring in chicken ipRGCs resembles that of rhabdomeric photoreceptors and involves phospholipase C (PLC) activation. In the current work we investigate the participation of the phosphoinositide (PIPs) cycle in this mechanism and probe whether changes in inositol 1,4,5-trisphosphate (IP3) and PIP kinase activities are triggered by light. Methods: We used primary cultures of Thy-1 immunopurified chicken embryonic RGCs exposed to bright light pulses or kept in the dark to assess intracellular Ca+2 mobilizatio