ABSTRACT
To investigate the pattern of neural differentiation and synaptogenesis in the mouse retina, immunolabeling, BrdU assay and transmission electron microscopy were used. We show that the neuroblastic cell layer is the germinal zone for neural differentiation and retinal lamination. Ganglion cells differentiated initially at embryonic day 13 (E13), and at E18 horizontal cells appeared in the neuroblastic cell layer. Neural stem cells in the outer neuroblastic cell layer differentiated into photoreceptor cells as early as postnatal day 0 (P0), and neural stem cells in the inner neuroblastic cell layer differentiated into bipolar cells at P7. Synapses in the retina were mainly located in the outer and inner plexiform layers. At P7, synaptophysin immunostaining appeared in presynaptic terminals in the outer and inner plexiform layers with button-like structures. After P14, presynaptic buttons were concentrated in outer and inner plexiform layers with strong staining. These data indicate that neural differentiation and synaptogenesis in the retina play important roles in the formation of retinal neural circuitry. Our study showed that the period before P14, especially between P0 and P14, represents a critical period during retinal development. Mouse eye opening occurs during that period, suggesting that cell differentiation and synaptic formation lead to the attainment of visual function.
ABSTRACT
AIMS: Our aim is to investigate the effects of prenatal alcohol exposure (PAE) on the development of retinal bipolar and horizontal cells. METHODS: The alterations of the retinal bipolar and horizontal cells in P7, P14 and P30 mice were observed after PAE, with immunofluorescent labeling and DiI diolistic assay. RESULTS: The retinal development of filial pups was affected by PAE in a dose-dependent and long-term manner. The number of bipolar cells of alcohol groups was significantly lower than that of the control, and the dendritic receptive field of horizontal cells was also significantly smaller than those of the control groups (P < 0.01). CONCLUSION: PAE was able to cause retarded development of pup retinal neural cells.
