title: L-dopa methyl ester attenuates amblyopia-induced neuronal injury in visual cortex of amblyopic cat.
abstract: In the present study, we aimed to assess the potential anti-amblyopic effects of L-dopa methyl ester (LDME) on visual cortex area 17 in an amblyopic feline model induced by monocular vision deprivation. After LDME administration, pathophysiologic and ultrastructural observations were utilized to examine the morphological changes of nerve cells in visual cortex area 17. Dopamine (DA) and its metabolite contents in visual cortex area 17 were investigated through HPLC analysis. Apoptotic cells in visual cortex area 17 were evaluated by TUNEL assay. Additionally, the c-fos expression both at gene and protein levels was assessed using RT-PCR and immunohistochemistry analyses, respectively. The contents of DA and its metabolites were elevated in visual cortex area 17. Neuronal rejuvenation which occurred in visual cortex area 17 was observed through anatomical and physiological assessments. Similarly, TUNEL results showed that neuronal apoptosis was inhibited in the visual cortex of amblyopic cats by both L-dopa and LDME therapies. Meanwhile, the c-fos expression was notably up-regulated at both the mRNA and protein levels by the treatments. These findings suggested that LDME treatment could effectively increase DA and its metabolite contents, and restrain the apoptotic process, as well as elevate the c-fos expression in nerve cells of visual cortex area 17. Taken together, LDME might ameliorate the functional cytoarchitecture in visual cortex area 17 through mechanisms that elevate DA content and increase endogenous c-fos expression, as well as inhibit neuronal lesion in visual cortex tissue.
authors.affiliation: Department of Pharmacology, Guangxi Medical University, Nanning, Guangxi 530021, PR China.
authors.forename: Rong
authors.initials: R
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Liang
authors.forename: Zhaoni
authors.initials: Z
authors.lastname: Chen
authors.forename: Shijun
authors.initials: S
authors.lastname: Zhang
authors.forename: Xing
authors.initials: X
authors.lastname: Lin
authors.forename: Renbin
authors.initials: R
authors.lastname: Huang
mesh_terms: D000550:Amblyopia / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002415:Cats; D004298:Dopamine / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D007980:Levodopa / Q000008:administration & dosage / Q000031:analogs & derivatives*; D009474:Neurons / Q000378:metabolism / Q000502:physiology; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects; D014793:Visual Cortex / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D007980:Levodopa; C035420:levodopa methyl ester; D004298:Dopamine
keywords: 3,4-dihydroxyphenylacetic acid; ANOVA; AP-1; Amblyopia; BBB; CNS; DA; DAB; DOPAC; Dopamine; EDTA; HPLC; HVA; LDME; PBS; RT-PCR; SD; TEM; TUNEL; Visual cortex area 17; activator protein 1; blood–brain barrier; c-fos; cDNA; central nervous system; complementary deoxyribonucleic acid; diaminobenzidine; dopamine; ethylene diamine tetraacetic acid; high performance liquid chromatography; homovanillic acid; l-Dopa methyl ester; l-dopa methyl ester; mRNA; messenger-ribonucleic acid; one-way analysis of variance; phosphate buffer solution; reverse transcription-polymerase chain reaction; standard deviation; terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling; transmission electron microscopy