ABSTRACT
@#Objective To study the brain cell injuries and behavioral changes of newborn rats with kernicterus. Methods Twenty-five 5-day-old Sprague-Dawley rats were divided into control group (n=11) and model group (n=14) radomly. The model group was injected with bilirubin solution 10 μg/g in the cisterna magna, while the control group was injected with equal volume of normal saline. The neurobehavioral changes were observed and the body mass were recorded. TUNEL staining was used to check the apoptosis of striatal nerve cells of basal ganglia in the model group (n=3) on the first day after modeling. The remaining rats were assessed by gait analysis and beam-walking test 19 days after birth, and Morris water maze test was performed 30 days after birth. Results The model group showed apparently abnormal neurobehavioral changes, such as clenched fists, opisthotonos and the body mass were significantly lower in the model group than in the control group (F>27.707, P<0.001). TUNEL staining showed striatal nerve cells apoptosis in the model group. For the gait analysis, the step lengths of both hind legs were shorter (t>4.129, P<0.01), and the difference of step length was longer (t=-4.415, P<0.001) in the model group than in the control group, however, there was no significantly difference in the step width between two groups (t=0.462, P=0.649). For the beam-walking test, the score was lower in the model group than in the control group (t=-3.644, P=0.004). For the Morris water maze test, the escape latency was longer (F>6.206, P<0.05), and the number of crossing platform was less (t=3.297, P=0.004) in the model group than in the control group. Conclusion The newborn rats' model of kernicterus showed deficits in multiple motor functions and learning and memory ability, which could be assessed by gait analysis, beam-walk test and Morris water maze test, respectively.
ABSTRACT
Objective To assess the influence of transcranial electric stimulation (TES) on the recovery of motor function after cerebral focal ischemia and reperfusion and to explore the mechanisms in terms of neural plasticity.Methods An acute focal ischemia-reperfusion model was established by transient occlusion of the right middle cerebral artery (MCAO).Seventy-two male Sprague-Dawley rats were randomly divided into a TES group,a model group,a sham-operation group and a normal group.The TES group was given TES 24 h after MCAO;the model group received the operation without any treatment.Forelimb placing (FPT) and beam walking (BWT) were mea-sured at the 3rd,7th,14th and 28th day after reperfusion.Microtubule-associated protein-2 (MAP-2) and growth-associated protein-43 (GAP-43) and grey levels of reaction products in the peri-infarct region were examined by immunohistochemical techniques.Results The TES group rats had markedly better FPT and BWT performance at the 7th,14th and 28th day after MCAO,compared with the model group.Expression of MAP-2 had increased significantly more at the 14th and 28th day in the peri-infarct region in the TES group compared with the model group.Expression of GAP-43 was significantly elevated in the peri-infarct region in the TES group compared with the model group at all time points.Conclusions TES can improve motor function and neural plasticity following cerebral ischemia and reperfusion damage.The functional enhancement may be partly due to up-regulation of the expression of GAP-43 and MAP-2 in the peri-infarct region.