How viagra makes men loving as well as lusty
By DANIEL MARTIN
Anti-impotence drugs can turn men into more loving partners, new research suggests.
As well as its original aim of improving sexual performance, Viagra boosts levels of a "cuddle chemical" in the brain that increases a man's love for his partner.
Scientists have found that the little blue pill stimulates production of the love hormone oxytocin, which is believed to promote romantic feelings and bonding between couples.
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'Viagra may make a man more loving as well as improve his physical performance'
The chemical is released during orgasm and also has an important role in social interaction, childbirth and breastfeeding.
The discovery that anti-impotence drugs can also make men love their women more was made by scientists from the University of Wisconsin-Madison in the US.
Study leader Proefssor Meyer Jackson, said: "This is one piece in a puzzle in which many pieces are still not available.
"But it raises the possibility that erectile dysfunction drugs could be doing more than just affecting erectile dysfunction."
Viagra overcomes impotence by blocking phosphodiesterase type 5, a chemical that limits blood flow. Scientists have now discovered that this chemical also regulates the release of 'love hormones' in the brain.
Viagra: boosts levels of a 'cuddle chemical' in the brain
It means that Viagra effectively stimulates the brain to pump out more of this love chemical.
However, Professor Jackson warns that Viagra cannot make a man love a woman he has no feelings for. There has to be some affection there to start with.
"Erectile dysfunction drugs do not induce erections spontaneously, they enhance the response to sexual stimulation," he said.
"The same thing is happening in the posterior pituitary - Viagra will not induce the release of oxytocin on its own, but it will enhance the amount of release you get in response to electrical stimulation.
"I think this is a missing link in terms of trying to sort out the issues around whether there are additional effects of phoshodiesterase type 5 inhibitors."
Two other drugs, Levitra and cialis, work in the same way by blocking the same enzyme - meaning they are likely also to increase levels of love chemicals in men.
The discovery, to be published in the Journal of Psychology, was made by measuring levels of oxytocin produced by rats.
When the rats' pituitary glands were exposed to Viagra, they released three times more oxytocin than they did without the drug.
Professor Jackson said because oxytocin is well-known for its ability to promote the forging of strong social bonds, it may also provdie a biological explanation for why people fall in love, especially after sex.
The study is one of many investigating the beneficial side-effects of anti-impotence drugs. Another recent study has shown that Viagra helps hamsters overcome jetlag. But Argentinian scientsists found it only applied to flights going east.
A trial is underway to find out whether Viagra can help reduce the numbers of premature babies. Mums-to-be are being given the drug to increase the blood supply to the womb, allowing the baby to get all the nutrients they need.
And another study is looking at whether the drug can be used to help men with chronic hip pain.