A system for rapid, local superfusion of cultured neurones and their neurites with various different test drugs is elucidated.
An area of down to 30 μm diameter was superfused with the aid of two micropipettes, one for delivering the test solution and
the other for its removal. Active removal of solution within the dead-space of the delivery pipette guarantees, on the one
hand, fast and flexible pressure control and, on the other, enables the quick exchange (<1 s) of multiple solutions. By increasing
the pressure in the superfusion pipette, the laminar stream between the pipettes was forced down onto the cell layer. The
change from bath to superfusion solutions, evaluated by liquid junction potential changes, occurs in the order of 1 ms.
Key words Local superfusion - Whole-cell patch clamp - Solution changes - Fast perfusion - Cultured neurones