ABSTRACT
Objective To explore the effects of constraint-induced movement therapy (CIMT) on the expression of tyrosine hydroxylase (TH) and glial cell derived neurotrophic factor (GDNF) in Parkinson's disease (PD) model rats. MethodsPD models were established by microinjection of 6-hydroxydopamine (6-OHDA) solution into substantia nigra of rats' right cerebral hemisphere.Forty-two model rats were divided randomly into an exercise group and a control group 1 week after microinjection.The exercise group rats were forced to use their impaired limbs by placing their nonimpaired fore-limbs in casts.The control group rats were housed in the same environment without any special treatment.Two weeks after 6-OHDA infusion and exercise training,the behavioral changes of rats were examined after intraperitoneal injection apomorphine ( APO).The content of dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) was measured by high performance liquid chromatography with electrochemistry ( HPLAEC) ; the expressions of TH and GDNF in striatum were detected by immunohistochemical methods and TH,GDNF mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR).Results After 2 weeks of training,the rotating laps of the rats in exercise group within 30 min after APO induction,reduced to a significantly greater extent when compared to the control group (P ＜ 0.05).The content of DA and it's metabolites DOPAC in striatum homogenate was significantly higher in exercise group than that in the control group ( P ＜ 0.05 ),and the expression levels,of TH and GDNF protein/ mRNA were also significantly higher in the exercise group than those in control group ( P ＜ 0.05 ).Conclusions CIMT can improve the behavioral performance of PD rats,probably through promoting the expressions of TH and GDNF protein/mRNA in striatum,and increasing DA and it's metabolites DOPAC level.
ABSTRACT
<p><b>OBJECTIVE</b>To examine the effect of estrogen on the expressions of phosphorylated Tau (P-Tau), ChAT and nerve growth factor (NGF) protein in the brain tissue of rat models of Alzheimer disease (AD).</p><p><b>METHODS</b>Rat models of AD were established by injecting Aβ1-42 protein fragments in the right lateral ventricle. Two weeks later, 17β-estradiol tablets were implanted subcutaneously at the neck of the rats and maintained for 30 days. The pathological changes in the rats' brain neurons and alterations in the expressions of P-Tau, ChAT and NGF proteins were observed using HE staining and immunohistochemistry, respectively.</p><p><b>RESULTS</b>In the AD rats, neurofibrillary tangles occurred in the brain tissue, and estrogen treatment significantly reduced the formation of neurofibrillary tangles. Estrogen treatment also resulted in lowered P-Tau expression and increased ChAT and NGF protein expressions in comparison with those in the AD model rats.</p><p><b>CONCLUSION</b>Estrogen can up-regulate ChAT and NGF and down-regulate tau protein expression, thus producing obvious therapeutic effect on AD in rats.</p>