Question

3. Show here are two patch clamp recordings of ion channel activity: Da Inn minn a. What is the difference between the top and bottom recordings? What do they indicate? b. What is patch clamping? Explain how the technique works. c. Hypothesize as to why ion channel activity might switch from the top recording to the bottom recording.

Answer 1

A. The difference in two patch clamp is the unit of current flowing. In the second picture the channels are closed indicated of zero current flow. A patch clamp recording of current reveals transitions between two conductance states of a single ion channel: closed (at top) and open (at bottom).

B. The patch clamp technique is a laboratory technique used to study ionic currents in individual isolated living cells, tissue sections, or patches of cell membrane. The technique is especially useful in the study of excitable cells such as neurons, cardiomyocytes, muscle fibers, and pancreatic beta cells, and can also be applied to the study of bacterial ion channels in specially prepared giant spheroplasts.

Patch clamping can be performed using the

• voltage clamp technique
• The current clamp technique

In this technique, the voltage across the cell membrane is controlled by the experimenter and the resulting currents are recorded and vice versa.

C. These activities may get switched due the difference in the action potential of the membrane