Purchase this article with an account.
ZQ Yin, YB Liu, YL Tu1, PF Gao1; Experience-dependent Changes of the PSCs in Visual Cortex Neurons of the Developing Rat . Invest. Ophthalmol. Vis. Sci. 2002;43(13):4772.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To study the experience-dependent synaptic plasticity on cells from different layers of rat visual cortex before and after eye-open day. Methods: The visual cortex slices were prepared from 35 Sprague-Dawley rats of both genders (4∼28 days). Bipolar stimulating electrodes were placed in white material of the visual cortex. Recording electrodes filled with 0.5% biocytin were positioned in II∼VI layers. Blind whole cell patch recording technique was adopted. Postsynaptic currents (PSCs) were evoked with interstimulus intervals of 0.1 Hz. Recordings were obtained using a voltage clamp amplifier and pClamp6 software. The neurons were stained after recording for the purpose of morphological study. Results: (1) There were three types of PSCs recorded from 156 cells: non-response PSCs, monosynaptic response PSCs and polysynaptic response PSCs, during the first postnatal month. Before the rat’s eye-open day, the ratio of the non-response PSCs recorded from neuron of visual cortex was significantly higher (57.3%) than those after the eye open (11.9%) (p<0.001). Meanwhile, the incidence of polysynaptic response PSCs was increased from12.4% before the eye open to 28.9% after eye open (p<0.01). (2) In layer IV after eye open, the input resistance of the neurons was decreased and the half-width of PSCs was prolonged (p<0.01) comparing with recordings before eye close period. The peak value, time of peak, 10∼90% rise time and 10-90% decay time of PSCs was increased significantly (p<0.05 ∼ p<0.001). The changes of input resistance and peak value of PSCs were also observed in layer II-III (p<0.001) after the rat eye open. (3) 23 cells were intracellular stained with Biocytin. The higher IR, more depolarized RMP, non-response or lower amplitude of PSCs was recorded from cells that were morphologically immature. Conclusion: (1) the conversion of silent synaptic responses to functional ones might play a major role in experience-dependent synaptic plasticity during development of the visual cortex. (2) The functional and morphological maturity of neurons in visual cortex of rat was coincided with age.
This PDF is available to Subscribers Only