PURPOSE  To investigate dark-rearing’s effect on the temporal window of Spike-timing Dependent Plasticity (STDP).
METHOD  Visual cortical slices from 3- to 4-week-old C57BL/6 mice reared in normal light/dark 12 hr cycles or in the dark for 2 days with care provided under infrared illumination. Spike-timing-dependent plasticity was induced in layer II/III cells by pairing presynaptic stimulation (in layer IV) with postsynaptic burst firing evoked by four brief suprathreshold current pulses. We observe synaptic plasticity changes by different timing sequences and intervals of the pre- and postsynaptic spikes. Bath application of NR2b specific antagonist Ifenprodil shorten dark exposure mice’s temporal window into normal one.
RESULT  The temporal window of dark reared animals extend to -200ms~100ms, comparing to the time window of (-100ms~50ms ) of normal mice.NR2b plays an important role in this phenomenon.
CONCLUSION Dark-rearing, as a special visual deprivation, extends the temporal window of STDP and NR2b plays a key role in this kind of extension, which open a new door to explore the mechanisms under visual development and visual deprivation.