ABSTRACT
The purpose of this study was to observe the expression of LINGO-1 after cerebral ischemia, investigate the effects of retinoic acid (RA) on the expression of LINGO-1 and GAP-43, and the number of synapses, and to emplore the repressive effect of LINGO-1 on neural regeneration after cerebral ischemia. The model of permanent focal cerebral ischemia was established by the modified suture method of middle cerebral artery occlusion (MCAO) in Sprague-Dawley (SD) rats. The expression of LINGO-1 was detected by Western blotting and that of GAP-43 by immunohistochemistry. The number of synapses was observed by transmission electron microscopy. The SD rats were divided into three groups: sham operation (sham) group, cerebral ischemia (CI) group and RA treatment (RA) group. The results showed that the expression level of LINGO-1 at 7th day after MCAO in sham, CI and RA groups was 0.266 ± 0.019, 1.215 ± 0.063 and 0.702 ± 0.081, respectively (P<0.01). The number of Gap-43-positive nerve cells at 7th day after MCAO in sham, CI and RA group was 0, 59.08 ± 1.76 and 76.20 ± 3.12 per high power field, respectively (P<0.05). The number of synapses at 7th day after MCAO was 8.42 ± 0.13, 1.74 ± 0.37 and 5.39 ± 0.26 per μm², respectively (P<0.05). It is concluded that LINGO-1 expression is up-regulated after cerebral ischemia, and RA inhibits the expression of LINGO-1, promotes the expression of GAP-43 and increases the number of synapses. It suggests that LINGO-1 may be involved in the pathogenesis of cerebral ischemia, which may provide an experimenal basis for LINGO-1 antogonist, RA, for the treatment of cerebral ischemia.
Subject(s)
Animals , Male , Rats , Blotting, Western , Brain Ischemia , Metabolism , GAP-43 Protein , Genetics , Metabolism , Gene Expression , Membrane Proteins , Genetics , Nerve Tissue Proteins , Genetics , Neurons , Metabolism , Rats, Sprague-Dawley , Tretinoin , PharmacologyABSTRACT
The purpose of this study was to observe the expression of LINGO-1 after cerebral ischemia, investigate the effects of retinoic acid (RA) on the expression of LINGO-1 and GAP-43, and the number of synapses, and to emplore the repressive effect of LINGO-1 on neural regeneration after cerebral ischemia. The model of permanent focal cerebral ischemia was established by the modified suture method of middle cerebral artery occlusion (MCAO) in Sprague-Dawley (SD) rats. The expression of LINGO-1 was detected by Western blotting and that of GAP-43 by immunohistochemistry. The number of synapses was observed by transmission electron microscopy. The SD rats were divided into three groups: sham operation (sham) group, cerebral ischemia (CI) group and RA treatment (RA) group. The results showed that the expression level of LINGO-1 at 7th day after MCAO in sham, CI and RA groups was 0.266±0.019, 1.215±0.063 and 0.702±0.081, respectively (P<0.01). The number of Gap-43-positive nerve cells at 7th day after MCAO in sham, CI and RA group was 0, 59.08±1.76 and 76.20±3.12 per high power field, respectively (P<0.05). The number of synapses at 7th day after MCAO was 8.42±0.13, 1.74±0.37 and 5.39±0.26 per μm(2), respectively (P<0.05). It is concluded that LINGO-1 expression is up-regulated after cerebral ischemia, and RA inhibits the expression of LINGO-1, promotes the expression of GAP-43 and increases the number of synapses. It suggests that LINGO-1 may be involved in the pathogenesis of cerebral ischemia, which may provide an experimenal basis for LINGO-1 antogonist, RA, for the treatment of cerebral ischemia.