RESUMEN
Subcutaneous delivery of nicotine was performed using a novel electrically-operated needle-free jet injector, and compared to hypodermic needle delivery in a porcine model. Nicotine was delivered as a single, one-milligram dose into the abdominal skin, formulated as a 50 microliter aqueous solution. Plasma levels of nicotine and cotinine, its main metabolite, were then monitored over 2â¯h, following which the injection site was excised for histological examination. No irritation or tissue damage were found at the injection sites, and the jet-injected nicotine exhibited comparable absorption into the systemic circulation to that injected using a conventional needle and syringe. The needle-free jet injection of nicotine is a promising and well tolerated method. The data presented from this porcine model will support a first in human trial towards a new promising nicotine replacement therapy.
Asunto(s)
Inyecciones a Chorro/métodos , Inyecciones Subcutáneas/métodos , Nicotina/administración & dosificación , Animales , Cotinina/sangre , Femenino , Modelos Animales , Agujas , Nicotina/sangre , PorcinosRESUMEN
The ability to record from the same neuron for extended periods of time is essential to understanding how the brain reorganizes during learning. Conventional chronic recording microelectrodes are made from metal or silicon. However, the large stiffness mismatch between the electrodes and brain tissue causes shear-induced inflammation, limiting long-term recording stability. The flexibility of polypyrrole microwire has the potential to improve the chronic recording stability by minimizing the stiffness mismatch. In this paper, we report the implantation of a conducting polymer microwire electrode in a rodent brain, and the successful recording of cortical activity using such an electrode.