| In vivo electrochemistry is a relatively new area of research involving the disciplines of analytical chemistry, physiological psychology, neurochemistry, and pharmacology. The work presented here includes the design and construction of instrumentation for in vivo electrochemistry, solution and in vivo characterization of micro-working electrodes, the use of the multi-electrode system for pharmacological and behavioral studies, statistical analysis of data, simulation studies, and the first chronoamperometric recording from a rhesus monkey.;Two studies were completed using the automated multielectrode system. An amphetamine dose/response study was conducted in which the electrochemical signal was monitored from four regions in the rat brain. Each animal received four injections over an 8 day period. Locomotor activity and stereotypy were monitored during each experiment, and these behavioral observations were correlated with the electrochemical signal.;Neurochemical activity in four regions of the rat brain was monitored while rats were feeding. This data was analyzed using various correlation techniques including cross correlation analysis.;Statistical analysis of chronamperometric data collected from chronically implanted graphite epoxy micro-electrodes (in rat brain) over a period of 5-8 days was conducted. Results indicate that an implanted electrode's response does not change from day to day and that chronically implanted electrodes are capable of monitoring neurochemical activity. The chronamperometric response of the electrodes to various brain constituents is shown as is the adherence of the electrodes to the Cottrell equation in vivo.;Two systems for computer controlled in vivo electrochemistry are described. One system consists of a commercial electrochemical system which has interfaced to a micro computer. The other system utilizes laboratory constructed potentiostat and amplifier circuitry, a micro-computer, and an analog multiplexer which permits recording from up to 16 electrodes in a single animal.;Computer simulation studies of in vivo electrochemistry were conducted to better understand the relationship of the observed response to the independent variables in the equation derived by Cheng et al. In vivo data collected using different values for some of the experimental parameters in the simulation equation was compared to simulated data.;Finally, chronoamperometric recordings were made from the brain of an unanesthetized rhesus monkey. The electrochemical signal increased during emotional excitation and feeding. |
