动物造模 z-bio 2021-07-06 711

　　Objective: To improve the success rate and accuracy of injection by studying the positioning method of nucleus tractus solitarius microinjection and applying various parameters for positioning injection.

　　Method: 15 rats were divided into vertical injection group, Bregma positioning group and lambda positioning group according to the experimental progress. In the vertical injection group, the needle insertion point was 0.5 mm at the front of the rat skull base, and the needle insertion depth was 7.5 mm. In the bregma positioning group, the needle entry point was bregma -11.0 mm, which was in the middle of both sides. The opening is 0.5-0.7mm, and the needle is inserted obliquely. The back angle is 24°, and the diagonal penetration depth is 8.6mm as the injection point. The λ positioning group uses λ-3.2mm, and the median on both sides is 0.5?. The needle entry point is 0.7mm, the diagonal puncture angle is 24° backward, and the depth is 9.6mm. After injection, observe the position of the fluorescent markers on the coronal section of the whole brain of each group of rats.

　　Result: The position of the fluorescent marker in the vertical injection group is located on the coronal section where the choroid plexus is located. The fluorescent markers in the bregma localization group were unstable, located in the cerebellum, the shallower brainstem, or the coronal part where the choroid plexus was located. In the lambda positioning group, the fluorescent labeling position of the rat weighing about 300 g was in the gap between the cerebellum and the brainstem, and the rat weighing about 400 g could accurately label the solitary nucleus.

　　Conclusion: In a 400g rat, use λ as the reference point to pierce the nucleus tractus solitarius obliquely at a certain angle to accurately inject into the nucleus tractus solitarius.