Resistive artifacts in liquid-ion exchanger microelectrode estimates of Na+ activity in epithelial cells.
In experiments on the rabbit urinary bladder epithelium we have identified an electrical artifact in certain liquid ion-sensitive microelectrodes. This artifact arises from the high electrical resistance of the ion-sensitive resins which in some cases are comparable to the resistance of the microelectrode glass wall. For Na+-sensitive microelectrodes this situation led to shunting of the exchanger potential and consequently artifactually high calculations of intracellular Na+ in the rabbit urinary bladder epithelium. A method for minimizing this shunting effect is described. After reduction of the shunt the frequency response of the Na+-sensitive microelectrode was increased and the estimated ai Na+ was decreased to 7 mM.
D000818:Animals; D004848:Epithelium / Q000032:analysis; D008297:Male; D008839:Microelectrodes / Q000592:standards*; D011817:Rabbits; D012964:Sodium / Q000032:analysis*; D001743:Urinary Bladder / Q000032:analysis*
D012964:Sodium