动物造模 z-bio 2023-02-01 725

　　Objective To explore the localization method of microinjection to the nucleus tractus solitarius to improve the success rate and accuracy of injection by applying different parameters for positioning injection.

　　Method 15 rats were divided into vertical injection group, Bregma positioning group and Lambda positioning group according to the different experimental progress. In the vertical injection group, the needle entry point was 0.5 mm from the front edge of the rat skull base and the needle entry depth was 7.5 mm; in the Bregma positioning group, the needle entry point was Bregma-11.0 mm and the bilateral midline opening 0.5 to 0.7 mm, and the needle was punctured obliquely. The angle is 24° backward, and the oblique puncture depth is 8.6mm as the injection point; the Lambda positioning group uses Lambda-3.2mm, and the bilateral midline is 0.5~0.7mm as the needle entry point, and the oblique puncture angle is 24° backward. The depth of 9.6mm is the injection point. Observe the position of the fluorescent markers on the coronal section of the whole brain of rats in each group after injection.

　　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, and were located in the cerebellum, the shallower brainstem, or the coronal section where the choroid plexus was located. In the Lambda positioning group, the fluorescent labeling position of the rats weighing about 300g is located in the gap between the cerebellum and the brainstem, while the rats weighing about 400g can be accurately labeled on the nucleus tractus solitarius.

　　Conclusion In rats of about 400 g, oblique stabbing at a certain angle with Lambda as the reference point can be accurately injected into the nucleus of the solitary tract.