“…This method of drug delivery has been used extensively in research applications for the delivery of molecules to the inner ear and central auditory pathway for pharmacological, physiological, and therapeutic purposes. Typically, glass micropipettes are loaded with ionically charged solutions that contain a soluble substance such as neurotransmitters, agonists, antagonists (Arnold et al, 1996;Ostwald, 1992, 1995;Ehrenberger and Felix, 1992;Felix and Ehrenberger, 1992;Hurley and Pollak, 1999;Walsh et al, 1995), neurotrophins (Oestreicher et al, 2000), dyes, or anti-inflammatory agents. When current is applied to a metal electrode in the micropipette, small quantities of solution are expelled and drawn into the oppositely charged tissue.…”