Transcranial ultrasonography for assessment of hyperechogenicity in the substantia nigra of rats with Parkinson's disease treated by electro-acupuncture

Abstract

Objectives To assess the substantia nigra (SN) hyperechogenicity (SNH) of 6-hydroxydopamine (6-OHDA)-induced Parkinson's disease (PD) rats before and after electro-acupuncture treatment by transcranial sonography (TCS), detect the expression of tyrosine hydroxylase (TH) in the SN by immunohistochemistry and the changes of inflammatory factors IL-1β and TNF-α in serum, duodenum, and SN, and explore the value of TCS in the diagnosis and treatment of PD. Methods Sixty male SD rats were randomly divided into either a sham-operation group (15 rats) or a 6-OHDA group (45 rats). PD was induced by injecting 6-OHDA unilaterally into the SN. A total of 33 models were successfully established. They were randomly divided into a model group (16 rats) and an electro-acupuncture group (17 rats). Behavioral and ultrasonographic assessments were carried out on the 15th and 45th days after modeling. On the 45th day, four rats in each group were selected for immunohistochemical staining for TH, and the rest of the rats were used to collect heart blood and SN, and duodenum tissues for detection of IL-1β and TNF-α by ELISA. ANOVA and t-test were used to compare the differences among and between groups. Results SNH was observed in the injured SN of the model rats. After treatment, the area of injured SNH in the electro-acupuncture group was significantly less than that in the model group (t=4.01, P<0.05). TH positive area in the electro-acupuncture group was significantly increased compared with the model group (t=2.84, P<0.05). The levels of TNF-α in the serum and duodenum, IL-1β in the duodenum in the electro-acupuncture group were significantly lower than those in the model group (t=8.88, 7.64, and 10.86, respectively, P<0.05). Conclusion TCS can be used to successfully observe the manifestations of SNH in PD rats before and after electro-acupuncture treatment, suggesting that TCS can be used as one of the evaluation indicators for the diagnosis and treatment of PD. Key words: Parkinson′s disease; Ultrasonography, transcranial; Electroacupuncture; Gastrointestinal