If they become uncoupled, you're not going to get electrical conduction through that tissue, and the heart will stop beating, Muller-Borer explained. Heart muscle cells can become uncoupled when their oxygen supply is cut off, as happens during a heart attack. Other researchers have used voltage-sensitive dyes to study the flow of electrical signals through heart tissue. So once you flash the cells with the laser, the dyes become toxic and the cells die. You inject a current into the muscle and you measure the voltage between two electrodes along the path of that current flow.
Gap junctions affect that voltage.
But electrodes are not useful for studying how gap junctions work at the cellular level, Cascio said. The number and distribution of gap junctions are affected by these conditions and may contribute to some of the adverse consequences of these diseases. This research was supported by a grant from the National Institutes of Health and the American Heart Association.