The effect has been shown in the thalamus, which is part of the limbic system in the brain. This system is involved in behavioral and emotional responses.

This may explain several behavioural differences in women who smoke, including why they are more resistant than men to quitting smoking. This work is presented for the first time at the ECNP Congress in Vienna.

Lead researcher, Associate Professor Erika Comasco (Uppsala University, Sweden) said:

 “For the first time, we can see that nicotine works to shuts down the estrogen production mechanism in the brain of women. We were surprised to see that this effect could be seen even with a single dose of nicotine, equivalent to just one cigarette, showing how powerful the effects of smoking are on a woman’s brain. This is a newly-discovered effect, and it’s still preliminary work. We’re still not sure what the behavioural or cognitive outcomes are; only that nicotine acts on this area of the brain, however we note that the affected brain system is a target for addictive drugs, such as nicotine”.

The researchers, from Uppsala University in Sweden, worked with a group of ten healthy female volunteers. The women were given a commercially available nicotine dose intranasally, and at the same time were injected with a radioactive tracer attached to a molecule which binds to the enzyme aromatase: aromatase, also known as estrogen synthase, is the enzyme responsible for the production of estrogen. MRI and PET brain scans enabled the researchers to visualize both the quantity of aromatase and where it was located in the brain. The researchers found that a single dose moderately reduced the amount of aromatase in the brain. Read more here.

Pregnancy May Have Women Cutting Back on Smoking Before They Know They’ve Conceived

Pregnancy can be a big motivator for women to stop smoking. Now a new study suggests that at least some pregnant smokers start cutting back even before they know they’ve conceived.

The findings, researchers say, suggest there may be biological mechanisms during pregnancy that can blunt the desire for nicotine.

If true, understanding those processes could potentially lead to new ways to aid smoking cessation, according to the investigators. Read more here.