Intracranial Injection of Gut-Derived Microbial Metabolites in a Mouse Model

Gut-derived microbial metabolites, such as short-chain fatty acids or SCFAs, are known to have diverse effects on brain-mediated animal behavior.

To study this, take a syringe containing SCFAs secured to a microinjector pump and connected to an injector cannula via tubing.

Next, take an anesthetized mouse with a guide cannula implanted in its brain.

Insert the injector cannula inside the guide cannula.

Allow the animal to recover.

Place the freely moving animal in a novel cage and allow it to acclimate.

Then, start the administration of the SCFAs intracranially at a controlled rate over the desired period.

Record the animal's locomotive behavior using animal behavior video tracking software.

Anesthetize the mouse before removing the injector cannula.

Analyze the result to evaluate the effect of intracranial injection of SCFAs on animal behavior.

After anesthetizing the mouse, insert the commercial injector into the commercial guide cannula. Once the mouse is recovered from anesthesia, place it in a novel cage and allow it to explore for 35 minutes freely. Infuse SCFAs using a delivery rate of 7 nano liters per second for a target volume of 2,100 nanoliters in the first five minutes. Then press DIRECTION to the infuse mode and press RUN. After behavioral testing, remove the commercial injector from the commercial guide cannula.