Abstracto

Preparation of Durable Cannula for Intracranial micro-infusion of NeuroactiveSubstances in Small Animals

Santhosh Mayannavar, Rashmi KS, Keerthi Deshpande, Sheila R Pai, Ganaraja B

Intracranial infusion of neuroactive chemicals is routine method in neurophysiology research. We devised a simple, durable and reusable internal cannula for this purpose. The guide cannula, placed securely on the skull using Dental acrylic and securing screw, was fabricated from a needle of 22 gauge hypodermic needle. The internal cannula was fabricated from 30 gauge Dental needle, which has a white coloured hub. The length of this internal cannula will be enough to reach the nucleus when inserted through the guide cannula at the time of infusion process. We infused Orexin A into BLA by using this cannula assembly in overnight fasted rats, which increased the food intake significantly. On histological examination we found that the location of injection was as desired in the BLA. The guide cannula and the internal cannula fabricated by us appeared to be highly dependable. The dental needle has high temper and it does not change the shape like insulin needle with limited reusability. We conclude that this method of fabrication of internal cannula will be a better alternative to those fabricated from hypodermic needles.