FEB 14, 2019 5:15 PM PST

Seeing the Effect of Nicotine on Neurons

WRITTEN BY: Carmen Leitch

Cigarette smokers become addicted to nicotine, a highly addictive substance that is absorbed through the skin, mouth, and lungs when a person takes a puff. It then travels to the brain, and stimulates the production of epinephrine and dopamine, resulting in a pleasurable feeling. Nicotine can get inside of neurons and is thought to create a dependence on the substance by binding to receptors on a cellular organelle called the endoplasmic reticulum. While it’s known that the number of those receptors then increases, not much else is known about the process.

Researchers have now developed a sensor that lights up in the presence of nicotine, which enables them to watch how the molecule moves in cells. This work, led by Henry Lester, a professor of biology at Caltech, has been reported in the Journal of General Physiology. The video illustrates the action; as nicotine levels rise, the biosensor in the endoplasmic reticulum of the cell glows brighter.

The endoplasmic reticulum (ER) is involved in the synthesis of proteins and lipids. The receptors that bind to nicotine, nAChRs, are made there and then directed to neurons. When nicotine enters the brain, they attach to nAChRs and initiate a cascade of events that results in a feeling of happiness. Lester and others have found that the ER can hang on to some nAChRs, and those receptors are still able to bind to nicotine while in that organelle. 

The nicotine-sensing tool that the scientists created is a protein that can close and open, like a trap that encloses nicotine. When that happens, a fluorescent protein begins to glow, indicating where the nicotine is. The researchers can add these biosensors to different areas of the cell. In this study, it was added to the cell surface and endoplasmic reticulum.

In this image, a biosensor is targeted to a cell's endoplasmic reticulum and glows green in the presence of nicotine / Credit: Caltech/Lester laboratory

The team created movies of cells that carried these biosensors and found that nicotine moves into the ER within seconds of being near a cell. Nicotine affects the nAChRs, moving more of them to the surface and making cells more sensitive to nicotine exposure. Therefore, the more smoke a person inhales, the faster they feel the effects, which is a part of the addiction.

These movies were made using individual neurons growing in dishes, so the researchers want to look at this movement in live mice next. They are also working on more biosensors for molecules like opioids and antidepressants.

 

Sources: AAAS/Eurekalert! via Caltech, Journal of General Psychology

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
MAY 04, 2021
Cell & Molecular Biology
A Potential Weakness in SARS-CoV-2 is Caught on Video
MAY 04, 2021
A Potential Weakness in SARS-CoV-2 is Caught on Video
You can see the spike protein of the virus in action in this video.
MAY 09, 2021
Cell & Molecular Biology
Understanding Why High Salt Diets Can Damage the Kidneys
MAY 09, 2021
Understanding Why High Salt Diets Can Damage the Kidneys
Chronic kidney disease is estimated to affect about 700 million people around the world. High salt diets are known to ma ...
MAY 20, 2021
Genetics & Genomics
The rhAmpSeq™ CRISPR Analysis System for next-generation sequencing analysis of CRISPR edits
MAY 20, 2021
The rhAmpSeq™ CRISPR Analysis System for next-generation sequencing analysis of CRISPR edits
CRISPR genome editing generates double-stranded breaks (DSBs) in genomic DNA and is a targeted method by which to achiev ...
MAY 27, 2021
Neuroscience
Research Less Likely to Be True is Cited More
MAY 27, 2021
Research Less Likely to Be True is Cited More
Researchers from the University of California San Diego have found that non-replicable data is cited 153 times more ofte ...
JUN 01, 2021
Microbiology
A Closer Look at a Potential Bioweapon
JUN 01, 2021
A Closer Look at a Potential Bioweapon
Francisella tularensis is a naturally occurring bacterium found throughout the Northern Hemisphere that is extremely vir ...
JUN 08, 2021
Neuroscience
Simple Blood Test Can Detect Depression and Underlying Neurodegeneration
JUN 08, 2021
Simple Blood Test Can Detect Depression and Underlying Neurodegeneration
Researchers led by King’s College London have found that levels of a protein known as neurofilament light chain (N ...
Loading Comments...