动物造模 z-bio 2022-11-29 571

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

　　Methods Fifteen 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 anterior edge of the skull base was 0.5 mm, and the depth of the needle was 7.5 mm. The angle was backward 24°, and the oblique puncture depth was 8.6 mm as the injection point; in the Lambda positioning group, Lambda-3.2 mm and 0.5-0.7 mm lateral to the midline of both sides were the needle insertion points, and the oblique needle insertion angle was 24° backward, and the oblique puncture was used. The depth of 9.6mm is the injection point. The positions of fluorescent markers on the coronal section of the whole brain of rats in each group after injection were observed.

　　RESULTS: In the vertical injection group, the fluorescent labeling position was located in the coronal section of the choroid plexus. The fluorescent markers in the Bregma localization group were unstable, and were located in the cerebellum, the superficial part of the 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 was located in the gap between the cerebellum and the brainstem, while the rats weighing about 400g could accurately label the nucleus tractus solitarius.

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