Biomaterial Database

Selective release of nitric oxide from retinal amacrine and bipolar cells. 1998

M Neal, and J Cunningham, and K Matthews

OBJECTIVE To investigate the cellular origin of nitric oxide released from the rabbit retina in response to physiological stimulation with light. METHODS The release of nitric oxide from the retina was measured in rabbits anesthetized with urethane. An eye-cup was prepared and was filled with Krebs-Ringer bicarbonate. After washing for 45 minutes, 0.5 ml medium was placed in the eyecup. The medium was replaced every 10 minutes, and nitric oxide in the resultant samples was measured using nitrate reductase and a nitric oxide meter. RESULTS In the unstimulated dark-adapted retina there was a spontaneous resting release of nitric oxide (1.20 nmol/min). When the retina was stimulated for 10 minutes with flickering light there was an increase in nitric oxide release to almost double the resting release. Stimulation of the retina for 10 minutes with continuous light produced a similar increase in nitric oxide release. The exposure of the retina to L-amino-4-phosphonobutyrate (APB), which specifically blocks transmission between the photoreceptors and the depolarizing bipolar cells, abolished the evoked release of nitric oxide caused by flickering light and continuous light. In contrast, the nonselective excitatory amino acid antagonist cis-2,3-piperidinedicarboxylic acid (PDA) had no effect on the flicker-evoked release of nitric oxide, but it more than halved the release caused by continuous light. A similar differential effect on release was found with glycine, which abolished the nitric oxide release evoked with continuous light but did not affect the flicker-evoked release. The inhibitory effect of glycine was blocked by strychnine. CONCLUSIONS Nitric oxide was released in the retina by flickering light and by continuous light, but the two types of stimulation cause nitric oxide release from different cells. Because in the rabbit retina nitric oxide synthase occurs mainly in a subpopulation of amacrine cells and a few bipolar cells, our pharmacologic results suggest that continuous light causes nitric oxide release from amacrine cells, whereas flickering light evokes nitric oxide release from bipolar cells.

UI	MeSH Term	Description	Entries
D007395	Interneurons	Most generally any NEURONS which are not motor or sensory. Interneurons may also refer to neurons whose AXONS remain within a particular brain region in contrast to projection neurons, which have axons projecting to other brain regions.	Intercalated Neurons,Intercalated Neuron,Interneuron,Neuron, Intercalated,Neurons, Intercalated
D008027	Light	That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.	Light, Visible,Photoradiation,Radiation, Visible,Visible Radiation,Photoradiations,Radiations, Visible,Visible Light,Visible Radiations
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D009569	Nitric Oxide	A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.	Endogenous Nitrate Vasodilator,Mononitrogen Monoxide,Nitric Oxide, Endothelium-Derived,Nitrogen Monoxide,Endothelium-Derived Nitric Oxide,Monoxide, Mononitrogen,Monoxide, Nitrogen,Nitrate Vasodilator, Endogenous,Nitric Oxide, Endothelium Derived,Oxide, Nitric,Vasodilator, Endogenous Nitrate
D010775	Photic Stimulation	Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.	Stimulation, Photic,Visual Stimulation,Photic Stimulations,Stimulation, Visual,Stimulations, Photic,Stimulations, Visual,Visual Stimulations
D010875	Pipecolic Acids		Acids, Pipecolic
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D012160	Retina	The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.	Ora Serrata
D003623	Dark Adaptation	Adjustment of the eyes under conditions of low light. The sensitivity of the eye to light is increased during dark adaptation.	Scotopic Adaptation,Adaptation, Dark,Adaptation, Scotopic
D004791	Enzyme Inhibitors	Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.	Enzyme Inhibitor,Inhibitor, Enzyme,Inhibitors, Enzyme