title: A proposed route to independent measurements of tight junction conductance at discrete cell junctions.
abstract: Direct recording of tight junction permeability is of pivotal importance to many biologic fields. Previous approaches bear an intrinsic disadvantage due to the difficulty of separating tight junction conductance from nearby membrane conductance. Here, we propose the design of Double whole-cell Voltage Clamp - Ion Conductance Microscopy (DVC-ICM) based on previously demonstrated potentiometric scanning of local conductive pathways. As proposed, DVC-ICM utilizes two coordinated whole-cell patch-clamps to neutralize the apical membrane current during potentiometric scanning, which in models described here will profoundly enhance the specificity of tight junction recording. Several potential pitfalls are considered, evaluated and addressed with alternative countermeasures.
authors.affiliation: Department of Chemistry; Indiana University ; Bloomington, IN USA.
authors.forename: Lushan
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Chemistry; Indiana University ; Bloomington, IN USA.
authors.forename: Yuhan
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: Department of Chemistry; Indiana University ; Bloomington, IN USA.
authors.forename: Lane A
authors.initials: LA
authors.lastname: Baker
authors.affiliation: Department of Internal Medicine - Renal Division ; St. Louis, MO USA ; Center for Investigation of Membrane Excitability Diseases; Washington University Medical School ; St. Louis, MO USA.
authors.forename: Jianghui
authors.initials: J
authors.lastname: Hou
keywords: SICM; conductance; ion channel; patch clamp; tight junction