[Effect of Modified Constraint-induced Movement Therapy on Neurotransmitter Levels of Motor Cortex in Cerebral Ischemia-Reperfusion Injured Rats].

OBJECTIVE: To study the effect and mechanism of modified constraint-induced movement therapy (mCIMT) on motor function recovery in cerebral ischemia-reperfusion rats. METHODS: The rats were randomly divided into the control group and the mCIMT group, with 12 rats in each group. The left middle cerebral artery occlusion (MCAO) model was established by the Longa suture method. In the mCIMT group, the rats started continuous training for 14 d on the 7 th day after modeling. The unaffected limb was tied to the chest with elastic bandages, and the affected limb was trained in the compulsory runner equipment. In the control group, rats moved freely in the cage. The body mass of rats was recorded within 20 d after modeling, and behavior was assessed by the foot-fault test. Some of the rats were euthanized 18 d after modeling, and high performance liquid chromatography (HPLC) was used to detect monoamine neurotransmitters (5-hydroxytryptamine (5-HT), 5-hydroxyindoleacetic acid (5-HIVV), homovanillic acid (HVA) ), and amino acid neurotransmitters (glutamic acid (Glu), asparaginic acid (ASP), glutamine (Gln), glycine (Gly), taurine (Tau), gamma aminobutyric acid (GABA) ) in the motor cortex and striatum, respectively. Enzyme-linked immunosorbent assay (ELISA) was used to detect the expression levels of total P70 ribosomal protein S6 kinase (p70s6k) and p70s6k phosphorylated protein (p-p70s6k) in motor cortex and striatum, respectively. RESULTS: Compared with the control group, the body mass of rats in the mCIMT group was comparable (P >0.05) within 21 d after modeling, foot-fault rate of the mCIMT group was significantly lower at 17 d after modeling (P<0.05). At 18 d after modeling, compared with the control group, the level of 5-HIVV in the motor cortex increased significantly (P<0.05), and the relative content of amino acid neurotransmitters (the ratio of Glu) in the motor cortex including Gln, Gly, Tau and GABA to Glu increased significantly (P<0.05 or P<0.01) except for decreased ASP/Glu (P<0.05). Moreover, compared with the control group, the expression of p-p70s6k in the motor cortex of the mCIMT was significantly decreased (P<0.05). There were no significant differences in monoamine neurotransmitters and amino acid neurotransmitters in the striatum between two groups (P>0.05). CONCLUSION: mCIMT improved the motor function of MCAO rats, and the mechanism might be related to the increase of amino acid neurotransmitters and 5-HIVV and decrease of p-p70s6k expression in the motor cortex.

FTIR study of hydrogen bonds in coal under drop weight impact testing.

There are many hydrogen bonds in coal, which affect the chemical structure and properties of coal. FTIR has been applied to the characterization study of the hydrogen bonds of Dongpang coals, which were under drop weight impact. There exists five kinds of hydrogen bonds in the coal: free OH groups, OH...π, OH...OH, cyclic OH tetramers and OH...N. Absorption strength of intermolecular hydrogen bonds markedly declined after impact. Free OH groups mechanical-power chemical reacted in drop weight impact testing. The infrared spectrum were curve-resolved into their component bands. The absorption strength of various hydrogen bonds decreased with the increase of impact energy, but the trend was slowing. By statistical relationship between then, we find then complying with power function relationship. By comparing the exponents of fitted equations, we concluded that failure sensitivity sequence of hydrogen bonds to the impact: free OH groups > cyclic OH tetramers > OH...N > OH...π > OH...OH.