In Vivo Voltammetry and the Neurochemical Control of Movement and Blood Pressure

Abstract

The value of in vivo electrochemistry lies in its unique ability to provide nearly continuous measurement of neurotransmitter release from the functioning nervous system. Although the push—pull cannula has yielded important insights into the neurochemistry of dynamic brain function, the physical size of the cannulae, the relatively infrequent sampling periods, and the damage produced to normal brain structures have restricted its use. The new technique of brain dialysis produces less tissue damage than the open cannula system, but it is at present limited in its sampling frequency. Electrophysiology is valuable for studying unit activity in the brain of anesthetized animals, but the technical problem of holding a cell in an awake animal reduces its value for behavioral studies. Also, electrophysiology does not provide direct information about neurochemical events taking place in the brain. We have found that in vivo electrochemistry has been an invaluable tool in our studies of the dynamic neurochemical changes associated with movement and blood pressure regulation.