Vasopressin is a hormone formed in the hypothalmus and secreted by the pituitary gland in mammals. The hormone has a variety of effects when released, though it is used primarily to control water retention through reduction of urine output. Recent studies suggest that vasopressin has another interesting purpose, however, as it may affect the ability to form pair-bonds in some mammals.
When the body is dehydrated, it uses vasopressin as a way to regulate water in the body. By reducing and concentrating the amount of urine discarded, the hormone helps the body to reabsorb available water and keep organs functioning normally. This is considered the primary use of the hormone, but it is far from the hormone’s only ability.
If high amounts of vasopressin are released into the body via the pituitary gland, it can cause vasoconstriction. This process narrows the blood vessels and can temporarily increase blood pressure. If the body suffers a severe shock, such as those caused by trauma or a stroke, blood pressure can drop to dangerously low levels. The release of vasopressin can help restore the body to normal blood pressure and prevent or reduce the effects of shock.
Some recent studies have shown that the hormone may cause a variety of interesting neurological effects. In voles and rats, vasopressin has been shown to have considerable impact on sexual, mating, and parenting behaviors. It is also believed to be related to aggressive behaviors, most particularly those compatible with maternal or protective behaviors.
Animals known for monogamous behavior, such as prairie voles, exhibit higher levels of vasopressin than their polygamous counterparts. In humans, some studies have been done that claim to show a correlation between high levels of the hormone and happiness in monogamous relationships or marriage. These findings remain somewhat controversial, but most experts agree with the assessment that some relationship exists between monogamous tendencies and vasopressin levels.
Although the behavior of voles may seem to have little relation to that of humans, social relationships with other humans have proved vital to human survival throughout history. While humans tend to associate their affection or commitment to others as a result of their emotions, the influence of hormones such as vasopressin on creating and continuing emotional relationships is a subject of consistent scientific study throughout the 20th and 21st centuries.
The body is a strange and wonderful organism, and extremely efficient in its use of available materials. While it may seem a bit odd that a hormone used primarily to control kidney function could also help you have a happy marriage, it is simply another example of the efficiency of the system. Ensuring a strong pair bond raises the likelihood of offspring with two parents to provide and protect them, therefore raising the likelihood of survival. Vasopressin, in addition to its useful abilities to regulate kidney function and provide necessary vasoconstriction, may also be a secret agent working to help you fall in love, and stay that way.