Effects Of A Natural Herb A On The Amblyopic Cats

ObjectiveTo study the effects of a natural herb A on the monocular form-deprived and strabismic cats with the technique of PVEP, SVEP and single cell unit recording.The morphological changes of the visual cortex were investigated by the HE stain,nissl stain and transmission electron microscope.Effects of the natural herb A were evaluated and the possible mechanism were discussed. Methods(1) Monocular form-deprived part.The cats were divided into five groups: a form-deprived group,a low-dose group,a high-dose group,a control group and a normal group.Each group had five cats.The left eyes were sutured in the form-deprived group for seven days.Afterwards,the sutured eyes in the control group were opened.In the same condition,the cats in the low-dose group and high-dose group received the natural herb A i.p. 10mg/kg and 30mg/kg for seven days separately.The PVEP, SVEP and the ocular dominance were compared among the groups.The characteristics of the right 17 area of the visual cortex were investigated under the lightscope and transmission electron microscope in each group.(2) Strabismus part.The cats were divided into five groups:a strabismic group, a low-dose group,a high-dose group,a control group and a normal group. Each group had four cats.Esotropia were lasted seven days in the left eyes.After then,the right eyes in the control group were sutured,under this condition the cats survived seven days.The natural herb A were administered in the low-dose group and high-dose group in the same manner as the form-deprived experiment. The PVEP, SVEP and the ocular dominance were investigated among the groups.The characteristics of the right 17 area of the visual cortex were studied under the lightscope andtransmission electron microscope. Results(1) The eletrophysiology of the monocular form-deprived part.The Pm latency and the N75.135 were the dominant changes in the PVEP.In the form-deprived group, the significant waves could not be recorded and the Pioo could not be marked in three cats.In addition,the waves were differentiated,the depth of the waves decreased and the Pioo latency delayed in the other two cats.The N75 of the left eyes in the low-dose group recoverd to the normal,however,the Pioo latency and the N75-135 did not reached the normal level.The high-dose group had regular waves.Additionally,The N75^ the Pioo latency and the N75.135 in this group recoverd to the normal level.The SVEP visual acuity in the control group and form-deprived group were worse than that in the normal group.However,that in the low-dose group and high-dose group recovered to the normal group.The ocular dominance in the form-deprived group was shifted to the right eyes,however,the phenomena did not occur in other groups.The binocular cells decreased in the form-deprived group,control group and low-dose group.Suprisingly,those in the high-dose group increased to the normal level.(2) The morphology of the monocular form-deprived part.In the form-deprived group,the neurons were injured and showed dysfunctionly.The neurons were recovered in the control group,low-dose group and high-dose group,especially in the latter.Moreover,the protuberance of the neurons were showed more in the low-dose group and high-dose group.(3) The eletrophysiology of the strabismus part.The amplitudes of the waves were decreased and there were no significant Pi00 latency delayed in the strabismic group.Compared with the normal group,there was no significant difference in the amplitudes of the left eye/right eye in the low-dose group and high-dose group.The SVEP visual acuity in the strabismic group and control group were worse than that in the normal group,while that in the low-dose groups and high-dose groups reached thenormal level.The binocular cells in the strabismic group and control group decreased,however,those in the groups administered the natural herb A increased to the normal level.(4)The morphology of the strabismus part.In the strabismic group,the neurons were showed dysfunctionly.The neurons in the control group were even worse than those in the strabismic group.Recovering signs was showed in the low-dose group and high-dose group,especially in the latter. Conclusions(1) The natural herb A can make the waves of PVEP in the form-deprived cats normalized. The N75^ Piooand N75.135 in the high-dose group reached the normal level.The SVEP visual acuity in the low-dose group and high-dose group is normal. The natural herb A can also increase the binocular cells to some extend.(2) The natural herb A has the effects of recovering the injured neurons and stimulating the protuberance of the neurons forming.(3) The natural herb A makes the ratios of the amplitude of the left eye/right eye normal.It can recover the SVEP visual acuity and increase the numbers of the binocular cells to the normal level in the strabismic cats.(4) The natural herb A has better therapic effects on the neurons in the high-dose group.The drug are proved to promote the protuberance of the neurons and strenghth the relationship of the synapses.(5) The natural herb A has the therapic effects on the form-deprived and strabismic amblyopic cats.