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Objective Motion detection is an important function of visual system.In the retina, three types (ON-, OFF-, ONOFF-) of direction-selective (DS) ganglion cells (DSGCs) have been found.For the ON-and ONOFF-DSGCs, accumulated results show that they receive DS synaptic input from a kind of interneuron, starburst amacrine cells (SACs).The asymmetrical inhibition between SACs and DSGCs is established around P8.Recent results indicate that visual experience, propagating cholinergic retinal wave and signal mediated by GABAA receptor after P7 are not crucial for the establishment of DS circuitry.But how the specific connection between DSGCs and SACs formed and what kind of mechanism took a part in the formation of this circuitry, are still unclear.The present work is to study the role of correlated spontaneous activity between DSGCs and SACs during the development of DS circuitry.Methods (1) Intravitreal injections of bicuculline methiodide (BMI), TTX and/or epibatidine were used to block GABAA receptor, retina spontaneous spikes and/or cholinergic waves during the development of rat retina from P0.(2) CTB-488 or CTB-594 was injected into the eyes to visualize the projection from retina to LGN.(3) Patch clamp recording was used to indentify DSGCs and collect data for analysis.Results (1) Daily injection is sufficient to block GABAA receptor, retina spontaneous spikes and/or cholinergic wave.(2) Projection area from treated eye has altered significantly in both side of LGN.(3) Both physiological and morphological properties of DSGCs have no significant changes in the treated retina.Conclusion Direction selectivity is established independently of correlated spontaneous activity in the retina.