PATCH CLAMP OF THE BASAL MEMBRANE OF BEETLE MALPIGHIAN TUBULES - DIRECT DEMONSTRATION OF POTASSIUM CHANNELS

The patch clamp technique was applied to Malpighian tubules of a tenebrionid beetle, Onymacris rugatipennis. Access to the basal membrane was achieved by a new method of stripping the tubules of the surrounding connective tissue. With 150 mM KSCN in the patch pipette, we obtained current records in the cell-attached configuration from basal K+ channels. The presence of these channels is consistent with the high K+ conductance previously demonstrated in the basal membrane of Onymacris Malpighian tubules. The peeling method described in this paper allows quick and easy preparation of Malpighian tubules for patch clamp studies on the basal cell membrane. © 1990.