Dissertation
Dissertation > Medicine, health > Ophthalmology > Ocular adnexal organ disease > Ocular disease and strabismus > Amblyopia

Effects of l-dopa Methyl Ester on the Strabismic Amblyopia Cats

Author LiYongWen
Tutor HuangRenBin
School Guangxi Medical University
Course Pharmacology
Keywords Strabismic Visual cortex Area 17 PVEP Treatment c-fos gene In situ hybridization FOS protein Nerve growth factor NOS positive cells
CLC R777.44
Type PhD thesis
Year 2010
Downloads 64
Quotes 0
Download Dissertation

Purpose: Amblyopia is a vision of the major diseases affecting children, one left untreated can lead to lifelong poor vision, its pathogenesis is still under exploration. 1990s, scholars of drug treatment of amblyopia conducted many clinical studies to current clinical use more levodopa therapy, and achieved certain results. However, there are many side effects of levodopa, poor tolerance, the effect of instability and other shortcomings. The experimental group after levodopa levodopa methyl ester obtained for structural reform (LDME). The purpose of this study is to observe LDME strabismic model for the therapeutic effects, to evaluate the treatment of amblyopia primary pharmacodynamic effects, discuss LDME mechanism of action. Methods: 30 normal kittens were randomly divided into six groups: low dose of levodopa methyl ester, medium-dose and high-dose group, model control group, positive control group and the normal control group, n = 5, at 4 weeks of age when the line eye lateral rectus resection cause artificial strabismus (except for the normal control group), the pattern visual evoked potential (P-VEP) to determine the formation of amblyopia after gavage given levodopa methyl ester 20mg/kg, 40mg/kg, 80mg / kg, positive control group given levodopa 40mg/kg, the normal control group and model group were given normal saline. Once a day for 30 consecutive days. ① The pattern visual evoked potential (PVEP) for each group of levodopa methyl ester function of the visual cortex of the cat; ② by HE Nissl staining, Nissl staining and transmission electron microscopy levodopa methyl groups cat visual cortex area 17 morphological changes; ③ situ hybridization visual cortex area 17 c-fos mRNA expression; ④ immunohistochemical detection of the visual cortex area 17 c-fos protein expression; ⑤ Immunohistochemical detection of visual cortical area 17 of nerve growth factor (NGF) expression; ⑥ detected by immunohistochemical techniques in visual cortex area 17 NOS-positive cell density. Results: ⑴ strabismic amblyopia part of the visual electrophysiological studies model control group (MC) mainly in the amplitude decreased P100 latencies and characterized, MC group latencies, latency compared with the contralateral eye and normal control group eyes latency significantly longer, the difference was statistically significant (P lt; 0.05); model control group each cat graphics amblyopia VEP P100 amplitude values ??and normal eyes with their normal ipsilateral eye compared, P100 amplitude smaller , the difference was statistically significant (P lt; 0.01). After treatment groups compared with the model group, latency shortened in varying degrees, to the most significant high-dose group, the difference was statistically significant (p lt; 0.01). By the use of drug treatment increased the amplitude of the amblyopic eye to the most significant high-dose group, compared with the normal control group, no significant difference (p gt; 0.05). Show levodopa methyl ester can significantly improve the model strabismic amblyopia conduction and sensory function. ⑵ part strabismic amblyopia morphological findings in model group (MC) 17 zone visual cortex neurons showed dysfunction, high-dose group, middle dose group and low dose group and positive control group of neurons in the recovery state, high dose recovery than the positive control group, middle dose group and low dose group. Particles inner, outer particles were recovered. ⑶ LDME area 17 on the visual cortex of c-fos mRNA expression in the visual cortex of the normal control group cat c-fos mRNA-positive cells were distributed widely expressed active. Hybrid cell distribution between the layers as: Ⅱ / Ⅲ, Ⅴ / Ⅵ layer high density, Ⅳ layer lowest density. Compared with normal control group, model control group amblyopia cat visual cortex c-fos mRNA hybrid cells were reduced at all levels, the difference was statistically significant (P lt; 0.01). Compared with the model group, the treatment group (including PC, LDMEL, LDMEM, LDMEH) c-fos mRNA hybrid cells in the visual cortex Ⅱ / Ⅲ, Ⅳ, Ⅴ / Ⅵ layer were increased, except in Ⅳ, the rest of the group the difference was statistically significant (P lt; 0.05 or P lt; 0.01), while the most obvious of which LDMEH group (P lt; 0.01). ⑷ LDME area 17 on the visual cortex Fos protein expression in the normal control group cat visual cortex area 17 full-thickness were seen Bao He puce-positive cells, NC cat visual cortex area 17 full-thickness were seen high levels of Fos protein expression, especially Ⅱ, Ⅲ, and Ⅵ layer density is high, Ⅳ and Ⅴ layer is low. Cat visual cortex model group full thickness can be seen positive cells between the layers and the distribution pattern similar to the normal control group, but the layers of positive cell density was significantly lower, the difference was statistically significant (P lt; 0.01). Treatment group (including the positive control group, levodopa methyl ester of high, medium and low dose group) distribution of positive cells basically in Ⅱ, Ⅲ, Ⅴ and Ⅵ layer, but the density of the treatment group than the model control group, the difference was significant and statistically significant (P lt; 0.05). Levodopa methyl ester treatment group and the positive control group compared to the treatment group levodopa methyl density layers of positive cells higher than the positive control group, the number of layers having a statistical significance. ⑸ LDME area 17 on the visual cortex of nerve growth factor (NGF) expression in model group amblyopia cat VC17 District NGF expression pattern changes, compared with the normal control group, model control group of endogenous NGF immunoreactive cells were reduced at all levels , there is a significant difference between the two (p lt; 0.01); by administering levodopa methyl ester hydrochloride treatment, NGF expression is increased in the treatment group (including the positive control group, levodopa methyl ester of high, medium and low dose groups ) compared with the model group, endogenous NGF immunoreactive cells were increased at all levels, in addition to LDMEL in Ⅲ, Ⅴ, Ⅵ, the remaining differences were statistically significant (p lt; 0.01 or p lt; 0.05); levodopa methyl group compared with the positive control group, NGF immunoreactive cells upward trend in the number of layers and LDMEH in Ⅲ, Ⅵ compared with the positive control group, the difference was statistically significant (p lt; 0.01 or p lt ; 0.05). LDMEH compared with normal control group, NGF immunoreactive cells in the layers are less than the normal group, but there was no significant difference between the two (p gt; 0.05) ⑹ LDME on the visual cortex area 17 NOS expression in the normal control group positive cells were mainly distributed in the gray matter Ⅱ, Ⅲ, Ⅳ, Ⅴ, Ⅵ layer and white matter, in the Ⅱ / Ⅲ layer up, Ⅴ / Ⅵ layer Secondly, Ⅳ layer minimum. Model group layers of visual cortex area 17 NOS positive cells in the distribution pattern similar to the normal control group, but the inner layers and layers of NOS positive fibers was significantly reduced, the model control group layers of visual cortex area 17 NOS-positive cell density were significantly decreased (P lt; 0.05), which Ⅱ / Ⅲ layer and Ⅴ / Ⅵ layer NOS-positive cell density corresponding to level with the normal group, the positive cell density difference is highly statistically significant (P lt; 0.01). After treatment the treatment group (including the positive control group, low dose of levodopa methyl ester school group) floors are restored to LDMEH most obvious. Conclusion: ⑴ levodopa methyl ester shortening of strabismic amblyopia P100 P100 wave latency and increasing amplitude, with improved strabismic amblyopia conduction and sensory function. ⑵ levodopa methyl ester strabismic neuronal damage has better therapeutic effect, high doses of the best, can speed up the replication, transcription, promote protein synthesis, so to restore the damaged neuronal morphology and can promote the formation of the cell body processes, to promote increased contact between synapses. ⑶ levodopa methyl ester can promote strabismic cat visual cortex area 17 c-fos mRNA expression; ⑷ levodopa methyl ester can promote strabismic cat visual cortex area 17 Fos protein. ⑸ levodopa methyl ester can increase strabismic cat visual cortex area 17 of nerve growth factor (NGF) synthesis and release. NGF expression changes coincide with PVEP prove levodopa methyl ester can strabismic amblyopic eye visual function to get some improvement. NGF as a factor regulating cell function, possibly developmental plasticity in the visual system play an important role. Levodopa methyl ester through NGF role in developmental plasticity in the visual system. ⑹ levodopa methyl ester, to some extent, improve the visual cortex of strabismic area 17 levels of nitric oxide. ⑺ levodopa methyl ester strabismic cats have a therapeutic effect, its therapeutic effect may be related to levodopa methyl ester promote strabismic cat visual cortex area 17 c-fos mRNA, Fos protein expression, increased nerve growth factor (NGF) synthesis and release and enhance the visual cortex of strabismic area 17 nitric oxide levels.

Related Dissertations
More Dissertations