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Recent research has offered some new insights into our biochemistry -- from a proposed drug for sexual arousal to a possible link between the flu and narcolepsy.

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You and I are, in a lot of ways, just bubbling cauldrons of chemicals. A whole lot of what we think and feel and experience during the day is the result of chemical compounds binding with tiny receptors all over our bodies, making us feel excited, scared, anxious or maybe just sleepy, and in the past couple of weeks, research has offered some new insights into our biochemistry.

Take the recent news that the U.S Food and Drug Administration may soon, for the first time, approve a drug designed specifically to cause sexual arousal. Last month an advisory panel recommended that the FDA green light a proposed drug called flibanserin, which is said to increase sexual desire in pre-menopausal women. It's been described in the media as "Viagra for women", which it isn't, really, mainly because Viagra doesn't actually affect a man's sex drive. Instead, it, and other drugs like it, are vasodilators, compounds that relax blood vessels to stimulate blood flow. They just help make erections possible when men are aroused. But flibanserin supposedly acts on the sex drive itself, helping to stimulate arousal in otherwise healthy women who feel little or no sexual desire.

The company behind the drug, called "Sprout", told the FDA that it doesn't exactly know how flibanserin works, but it seems to act partly as an agonist, or chemical that imitates the body's own signaling chemicals. In this case, they say it binds to receptors in the brain that are typically typically triggered by dopamine and norepinephrine, two of the more famously stimulating neurotransmitters that your body releases when you're excited and generally aroused.

At the same time, the drug also seems to act as an antagonist, or blocker of neurotransmitters that inhibit excitement, particularly serotonin, which regulates your sleep cycle. Some groups have praised the approval of the drug because they say it closes a gender gap in sexual medicine. While Viagra, and lots of other medications are available for male sexual health, there is nothing on the market that does the same for females, but, the results in the trials of flibanserin were only slightly better than placebos.

Three studies tested the drug on women who reported having what they described as "sexually satisfying events" two or three times a month. After 24 weeks of taking daily doses, women who took placebos reported an average of 1 more "sex event" every month, while those who took flibanserin reported about two and a half more, on average. But critics point out that there are side effects that come with altering your brain's chemistry, and in the drug's trials the most common were low blood pressure, dizziness and syncope, or the loss of consciousness, particularly in women who drink alcohol. The final decision on flibanserin will be made in August.

Meanwhile some other research into our biochemistry is shedding light on an unusual outbreak, an outbreak of narcolepsy. Narcolepsy is a disorder of the nervous system that can cause sudden, overwhelming fatigue and muscle weakness. It's most common symptom is a rather terrifying condition known as cataplexy in which a patient's voluntary muscle control briefly stops resulting in anything from drooping eyelids to total physical collapse. And it's typically triggered by strong emotions, whether it's a fit of anger or fear or even a big, strong belly laugh.

But in Europe, many physicians noticed that cases of narcolepsy started to increase in 2009 with about 1,300 cases being reported during the outbreak of the H1N1 flu. And last week a team of biologists said that they may have found a possible cause, a vaccine that was supposed to prevent the flu.

Vaccines work by stimulating the immune system to produce antibodies for the proteins found in certain viruses. Narcolepsy, meanwhile, is thought to be caused by a deficiency in a neurotransmitter called hypocretin. When it bonds to receptors in your brain, hypocretin makes you feel alert and awake. But the biologists found that the brain's receptors for hypocretin had a chemical structure that's very similar to one of the proteins found in the flu virus. And it turned out that the narcolepsy outbreaks were most common where a brand of vaccine called Pandemrix was used and Pandemrix contained a lot more of that particular protein. So the biologists think that when some people were injected with Pandemrix in 2009, their immune systems produced antibodies that bound to and labeled their wakefulness receptors for destruction causing them to suffer from narcolepsy.

Now the researchers aren't sure that the cause was the vaccine itself which in any case hasn't been used since 2010. Instead the real cause may have been those viral proteins no matter how they get into the body because similar spikes in narcolepsy in 2009 were reported in China where the vaccine was never used. And narcolepsy has also been associated with other flu pandemics including the infamous Spanish flu of 1917 and 1918. So taken together, this may be more evidence that narcolepsy is actually an autoimmune disease and that people who have it respond to infections by producing antibodies that attack their own hypocretin receptors. Because apparently getting the flu wasn't bad enough.

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