Home

A Day in the Lab: Unravelling Neuronal Activity using Electrophysiology

✍️ Author: Dr Eleni Christoforidou

🕒 Approximate reading time: 4 minutes

Today's adventure in the lab revolved around an electrophysiology experiment, with a particular emphasis on the patch-clamp technique. The underlying concept involves utilising an electrode to record the electrical activity of a solitary neuron grown in vitro. Admittedly, the procedure can initially seem somewhat challenging, but with practice, it becomes significantly more manageable. Over the past two months, I have successfully recorded activity from roughly 100 individual neurons, each requiring approximately 20 minutes of dedicated attention.

Presented below are images that depict what the neurons appeared like under the microscope. Further details on the experiment and the methods I employed are detailed subsequently.

These are some of the neurons from which I recorded electrical activity today. Image (A) illustrates a neuron under a DIC microscope. Images B-D display neurons labelled with a fluorescent reporter.
These are some of the neurons from which I recorded electrical activity today. Image (A) illustrates a neuron under a DIC microscope. Images B-D display neurons labelled with a fluorescent reporter.

To comprehend how neuronal activity is recorded and how to operate the recording equipment, one requires a solid understanding of physics and electronics. Electrophysiology demands it. Below, I've included an image of the various recording equipment utilised in today's experiment. The major components are labelled for the convenience of the curious among you. The setup principally involves a DIC (differential interference contrast) microscope connected to a range of electronic devices.

The array of equipment employed for my experiment.
The array of equipment employed for my experiment.

Delving into the Methodology of Today's Experiment

The recordings were performed employing a computer-controlled patch clamp amplifier, which was operated with specialised computer software. Whole-cell voltage clamp recordings were performed at a holding potential of -65 mV at room temperature. The whole-cell configuration was achieved by applying a gentle suction pulse orally while delivering a brief 1 V electrical pulse simultaneously. Compensation was applied for the fast and slow capacity transients. A seal test (a 10 mV test pulse) was administered through the recording electrode to measure the access resistance at the commencement of every 10-second recording.

Disclaimer: The information provided in this blog post is intended for educational and informational purposes only and should not be considered as a substitute for professional advice. While the author holds a PhD in Neuroscience and has extensive experience in the field, the content of this post may not be fully exhaustive or up-to-date, and in-text citations or a bibliography are not always provided. Readers are encouraged to consult relevant primary research articles, textbooks, and other reliable sources for comprehensive information on the topic. The author is not responsible for any errors or omissions, or for any actions taken based on the information provided in this post.

Published 28 Nov 2018