Chronic cocaine use modifies gene expression

[Chip (OP)]

source: https://neurosciencenews.com/cocaine-gene-expression-14850/

All drugs alter genes and is probably the underlying mechanism behind tolerance also.

Chronic cocaine use modifies gene expression

Chronic cocaine use alters the epigenetic profile of the FosB gene in the hippocampus. These alterations are required for cocaine-dependent gene expression and cocaine environment associations. Modification of hippocampal FosB results in a condition critical for cocaine-related learning.

Chronic cocaine use changes gene expression in the hippocampus, according to research in mice recently published in Journal of Neuroscience.

Chronic drug users learn to associate the drug-taking environment with the drug itself, reinforcing memories that contribute to addiction. These memories are thought to be created by changes in gene expression in the hippocampus and potentially involve the gene FosB, but the exact mechanism is unknown.

A.J. Robinson and colleagues at Michigan State University examined how cocaine exposure affected expression of the FosB gene in the hippocampus. Mice that were administered cocaine daily showed increased expression of FosB compared to mice that received saline.

Chronic cocaine use caused epigenetic modification of the gene, leading it to becoming more active.

Additionally, when the scientists blocked the changes made to FosB, the mice were unable to form associations between cocaine and the environment where they received it, implicating epigenetic regulation of the gene in drug memory formation.

Hippocampal neurons (green) expressing the FosB gene (red) after cocaine exposure

These results offer new insights in the molecular changes that take place in the hippocampus during chronic cocaine use. Further research in this area could lead to the development of addiction therapies.

[Olinmon]

What do they mean by chronic in this case?

[Chip (OP)]

Daily use.

The study doesn't say how long it ran but i would guess for a few months.