Effect of Tianzhi Granule on nigra and spinal cord dopaminergic neurons in mouse model of Parkinson's disease
Objective To investigate the effect of Tianzhi Granule on dopaminergic(DA)neurons in substantia nigra and spinal cord of Parkinson's disease(PD)mouse model.Methods PD mouse model was constructed by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine 25 mg/(kg·d)for five days in September 2022.The mice were randomly divided into the model group and the Tianzhi Granule 5,2,1 g/kg groups,with 10 mice in each group.Another 10 mice were taken as the normal control group.Af-ter two weeks of intragastric administration,the behavioral changes of mice in each group,the number and morphology changes of DA neurons in the substantia nigra and spinal cord,and the positive expression of tyro-sine hydroxylase in neurons were compared.Results Compared with the normal control group,the suspension ability of mice in the model group was decreased and the swimming time was shortened.After the intervention of Tianzhi Granule,the suspension ability of mice was effectively improved,the swimming time was pro-longed.The number of DA neurons in the anterior horn of the substantia nigra and spinal cord gray matter and the positive expression of tyrosine hydroxylase in neurons were significantly reduced.After five and two g/kg intervention with Tianzhi Granule,the detection indexes of DA neurons in the substantia nigra and spinal cord of mice were significantly improved,and the differences were statistically significant(P<0.05).Conclusion Tianzhi granule can improve the behavior of PD mice,increase the survival number of DA neurons and neurites in the substan-tia nigra and spinal cord,and increase the content of DA in the central nervous system,indicating that Tianzhi granule has a protective effect on dopaminergic neurons in the substantia nigra and spinal cord.