Abstract
Abstract: :
Purpose: A detailed knowledge of functional and structural organization of the mammalian retina under both physiological and pathological conditions is essential to understand normal retinal function and mechanisms of retinal disease. Methods: Using a new high speed (Nipkow spinning disk) confocal system, we conducted functional (Ca++) and structural imaging of living in situ retinal neurons in ex vivo retinal preparations (isolated retina and retinal slice). In combination with whole–cell patch clamp, optical imaging can be done simultaneously with electrophysiological recordings. Neuroactive agents were delivered rapidly and locally by a custom–made multi–channel local perfusion system. Results: Compared with conventional confocal systems, this new high speed confocal system is better suited for recording of fast physiological events and structure of living in situ neurons. Using this system we recorded robust Ca++ signals mediated by both voltage– and ligand–gated channels in in situ retinal ganglion cells (RGCs). In combination with whole–cell patch clamp, we also recorded simultaneously whole–cell currents elicited by both excitatory and inhibitory neurotransmitters and their agonists. Using long–working distance water immersion objectives we recorded confocal images of single (labeled with a fluorescent dye using the patch electrode) as well as multiple (labeled retrogradely at optic nerve) living in situ RGC(s). This high–speed confocal system also allows functional and structural measurements from the same in situ retinal neurons. Conclusions: This new high speed confocal imaging system, together with patch clamp and local perfusion techniques and ex vivo retinal preparations, provides a powerful tool to study normal retinal function and mechanisms of retinal disease. E
Keywords: imaging/image analysis: non-clinical • retina: proximal (bipolar, amacrine, and ganglion cells) • calcium