Study On The Character Of Morphology In The Development Of The Retinal Ganglion Cells Of RCS

Purpose: Royal college of surgeon rat (RCS) is a classical animal model of the heredity retinitis pigmentosa (RP). Retinal ganglion cells (RGCs)is the only cell that tranmit the signal to the optic centre in the retina. There has no documents about the research work of the morphology study about the RGCs of the RCS in the RP, so to study the change of the RGCs in the procedure of the RP is helpful to know the pathogenesis and pathological procedure of the RP. This experiment is to classified accouting the density of the RGCs and research the ultrastructure of the RGCs in the developmental retina of the postnatal(pn) RCS in the procedure of the RP. So the experiment is to initial researched the the character of morphology change in the RP of the RCS, and to deepen our knowledge about the pathogenesis of the RP.Methods: To separate the retina of the pn RCS and control group rat in the every weekage from pn3 weekage to pn12 weekage. After the whole mounted retina and staining retina with the cresyl violet, we analyzed those retina with the soft LEICA Q WIN of the LEICA DM TRET microscope and observed the different cells density in the retina of the RCS and control group rat according to the different standard including all cells in the retinal ganglion cells layer, cells that soma diameter≥12um and cells that soma diameter≥9μm in the retinal ganglion cells layer. With the transmission electron microscope, to study the character change of the ultrastructure of the RGCs in the pn3, pn5, pn7, pn9, pn11weekage retina of the RCS and the control group rat, accounted and compared the moderately swelling mitochondria in the RGCs of the RCS and the control group rat.Result: 1. There is no significant deviation about the density of the all cells in the ganglion cells layer of the RCS and the control group rat. To compare the density in the RCS group, the density of the pn5 weekage and pn6 weekage is significant less than the pn3 weekage and there is no significant deviation of other pn weekage.2. To compare the density of the RGCs, the density of the pn10 weekage of the RCS is significant more than the density of the same weekage of the control group rat and there isno significant deviation to compare the other weekage between the RCS and the control group rat. To compare the density in the RCS group, the density of the pnlO weekage is significant more than the pn3, pn5, pn6 and pnll weekage and there is no significant deviation of other pn weekage.3. To compare the density of the a hypotype of RGCs, some part of 3 and Y hypotype of RGCs, the density of the RCS is significant less than the density of the same weekage of the control group rat frame the pn4 weekage and the deviation is more significant in the pn7 weekage in the RCS. To compare the density in the RCS group, the density is significant less than the pn3 weekage from the pn7 weekage.4.To study the ultrastructure of the RGCs of the RCS and the control group with the transmission electron microscope, the result is the nucleoli and endoplasmic reticulum system still maintain the normal morophology in the procedure of the development of the RCS and the control group rat. No significant deviation have been found about it between the RCS and the control group rat. In the athological procedure, the density of the moderately swelling mitochondria in the RGCs of the RCS is more than the control group rat. The density of the moderately swelling mitochondria of the RCS is significant more than the same pn weekage of the control group rat from the pn5 weekage. To compare the density in the RCS group, the density is significant moer than the pn3 weekage from the pn5 weekage.Conclusion: With technology of the whole mounted retina and staining retina with the cresyl violet, to analyze the RGCs according to the different standard through the LEICA DM TRET microscope and with soft of computer counted, and analyzed the ultrastructure of the RGCs with the transmission electron microscope, the conclusion is:l.In the procedure of the RP of the RCS, the density of all ells in the ganglion cell layer is stable for the hyperplasia of the Miiller cells and the migration of the ectopia cells2. In the procedure of the RP of the RCS, the density of the a hypotype of RGCs, some part of P and Y hypotype of RGCs occured the deviation after the time of open eyes, and the ultrastructure of the RGCs of the RCS also occured the deviation. The deviation is more significant from the pn7 weekage, large amount of the RGCs is loss.3.To observe the ultrastructure of the RGCs with the transmission electron microscope, the nucleoli and endoplasmic reticulum system still maintain the normal morophology inthe procedure of the development of the RCS and the control group rat, but the extent of the swelling mitochondria is progressive intensified in the pathological procedure of RP. The time of this deviation occurred is concordance with the time of the descent of the density of the RGCs in the RCS.4. In the pathological procedure of RP, accompany with the degeneration and death of the photoreceptor cell, the density of the RGCs and the ultrastructure both occurred the deviation, and the deviation of the morphology is concordance with the change of the function, moreover, the change of the morphology is early than the abnormality of the function5. Through the experiment, we found there still some amount of RGCs survived in the pathological procedure of RP, and the nucleoli and endoplasmic reticulum system still maintain the normal morophology. So it have the possibility that those survival RGCs still remain the normal or some part of normal function and there is still chance for rescue and recondition the pathological retina.