Independent positioning of microelectrodes for multisite recordings in vitro

A robust and easy to handle, inexpensive multisite recording system is described which allows independent positioning of several microelectrodes with high precision axial movement of each electrode. The basic units of the system are a manually operated manipulator for left-right and up-down movement and a micrometer for positioning in the direction of the micrometer axis. The micrometer is actuated with a DC-motor operated by a stand-alone controller module allowing for remote control of the motor in either step mode or continuous mode. The multisite recording system has been proven to allow stable simultaneous recordings of single unit and population activities, extracellular ion concentrations and intracellular potentials in organotypic hippocampal slice cultures (OHSCs) of rat.