Purchase this article with an account.
Y.-C. Chan, C.-C. Chiao; Preferred Direction Distribution and Tracer Coupling Pattern of the ON-OFF Direction Selective Ganglion Cells at Around Eye Opening in the Rabbit Retina.. Invest. Ophthalmol. Vis. Sci. 2009;50(13):1427.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
In the adult rabbit retina, the ON-OFF direction selective ganglion cells (DSGCs) comprise four subtypes which respond to image motion in anterior, posterior, superior, and inferior directions (Oyster and Barlow, 1967). It has been suggested that the anterior subtype of the DSGCs may be the one that exhibits tracer coupling (Vaney, 1994). Although the direction selective responses are present at around the time of eye opening in rabbits (Masland, 1977; Zhou and Lee, 2005; Chan and Chiao, 2008), it is not clear if four subtypes of the DSGCs are well segregated at this stage and the tracer coupling pattern is adult like.
The DSGCs of New Zealand White rabbits at P10-12 were recorded extracellularlly to determine their preferred directions with respect to four cardinal axes. The recorded cells were subsequently injected with Neurobiotin for morphological identification and tracer coupling examination.
Despite the majority of DSGCs showed cardinal distribution of their preferred directions, about 20% of the cells were responding to non-cardinal directions at P10-12, which is much higher than 2% found in the adult rabbit retina (Oyster, 1968). Among those 20% of the recorded cells, their preferred directions distributed over all non-cardinal axes at around eye opening, which is different from those 2% of the cells reported in adult animals showing only anterior/inferior and posterior/superior non-cardinal axes (Oyster, 1968). For those DSGCs whose preferred directions showing cardinal distribution, the percentage of cells in each cardinal axis at P10-12 was similar to that of adult (Oyster, 1968). Furthermore, we found that the DSGCs with tracer coupling pattern at P10-12 did not confine to a single cardinal direction.
At around the time of eye opening, four subtypes of the DSGCs are not completely segregated, and the tracer coupling of the DSGCs is not subtype specific. This suggests that further fine tuning of the DSGC circuitry may be required after eye opening in the rabbit retina.
This PDF is available to Subscribers Only