Establishment of Osteoporotic Tree Shrew Model by Ovariectomy

  Objective: To replicate the postmenopausal osteoporotic tree shrew model using surgical bilateral ovarian castration. Methods: 100 female tree shrews were included in the experiment, and the model was modeled according to the "Guidelines for Clinical Diagnosis and Treatment of Primary Osteoporosis" (hereinafter referred to as "Guide") issued by the Osteoporosis and Bone Mineral Disease Branch of the Chinese Medical Association in 2011 Evaluation: ①According to the natural life span, sexual maturity time, peak bone mineral density (BMD) age and tree shrew natural life span and sexual maturity time, infer the peak month age of tree shrew BMD. Randomly select 6 tree shrews of 6, 12, 18, and 24 months of age for whole-body BMD testing, compare the differences in BMD of each month, and verify the peak age of BMD of tree shrews; ② Randomly select the peak age of BMD from the remaining tree shrews The 62 tree shrews were tested for BMD to determine the average and standard deviation of the BMD peak value of tree shrews. Then they were randomly divided into a model group (n=32) and a blank group (n=30).The model group was surgically removed both ovaries, and the blank group was removed with the same volume of omentum as the ovary. In June, September, and December, 6 animals were randomly selected for BMD testing, and those whose BMD values met the diagnostic criteria of the Guidelines were selected for pathological testing and verification. Results: ① The BMD peaks of the tested tree shrews at 6, 12, 18, and 24 months were (0.138±0.012), (0.143±0.010), (0.141±0.009), (0.139±0.009) g/cm2, each month There was no significant difference in the peak BMD of tree shrews (P>0.05); ②The average peak BMD of tree shrews was (0.143±0.016) g/cm2; ③The BMD values of the model group at each time point met the diagnostic criteria of the "Guide" for tree shrews The number of trabeculae was 0, 5, 4, and 5 respectively. The pathological section of the proximal tibia was compared with that of a 6-month-old tree shrew: the bone trabeculae were sparse and fractured, and the trabecular spacing was widened; the BMD value of each time point in the blank group was consistent with the The number of tree shrews according to the diagnostic criteria of the Guidelines is 0, and the pathological section of the proximal tibia is no abnormal compared with the 6-month-old tree shrew.

   Conclusion: According to the diagnostic criteria of the "Guide", a 6-month-old female tree shrew can replicate a human postmenopausal osteoporosis model 6 months after bilateral ovarian ovariectomy. The model has a high success rate and the model is stable.