Ask a physician what the hormone vasopressin is good for, and she will explain that it regulates the volume of water in your body and also affects blood pressure. But since the 1990s, vasopressin has
Given that one out of 68 children in the U.S. has an autism spectrum
disorder, researchers are scrambling to figure out what in the brain
might be related to the symptoms, and how they might design an effective
treatment. Vasopressin may be a key player in the disorder. But
scientists do not yet know whether too much or too little of the
hormone—or perhaps some combination of both—is tied to autism. New
clinical trials may yield insights. “I think that the work is exciting
and important” says Suma Jacob, who leads an autism research laboratory
at the University of Minnesota. “I also think we still have a lot more
work to do in this field as a whole.”
How vasopressin relates to autism
Previous research has shown that vasopressin, like the hormone oxytocin,
is associated with parenting behavior and social bonding, including
falling in love. In fact, the two hormones are structurally very
similar, and there are receptors in the brain that interact with both of
them. But high levels of vasopressin are also associated with anxiety
and aggression. Intriguingly, some animal studies have found that higher
levels of vasopressin increased aggression specifically in males. If
the hormone is indeed treated differently by receptors in the male brain
compared to those in the female brain, that’s all the more relevant for
autism: nearly five times as many boys have autism compared to girls,
according to the Centers for Disease Control and Prevention.
What’s more, vasopressin has also been linked to sensory processing in mammals.
Vasopressin neurons in the olfactory system may modulate input, sending
information about smells to behavioral areas of the brain. Other senses
also show connections to vasopressin, though they have been less
thoroughly studied. For instance, some research found that people who
received intranasal vasopressin showed an improvement in auditory
recall. In a review article published in Frontiers in Endocrinology,
Janet Bester-Meredith of Seattle Pacific University and her colleagues
explained that the effect probably stems from the hormone’s ability to
increase arousal. “Vasopressin may be essential for integration of
sensory input during complex forms of social behavior in mammals,” they
wrote. This connection is relevant to autism because the condition can
cause sensory overload and difficulty processing sensory information.
A study published in July in PLOS ONE, strengthens
the theorized connection between vasopressin and autism. A team of
Stanford University researchers compared the blood levels of vasopressin
in children with autism, their siblings who don’t have autism, and a
control group of unrelated children who do not have autism.
The study found varying vasopressin levels in all
three groups, meaning vasopressin by itself does not determine autism.
However, this biomarker did predict how well children in the autism
group performed on a test of “Theory of Mind” – the ability to perceive
the perspectives of others.
Specifically, autistic children with low
vasopressin levels performed poorly on this test. In children without
autism, low vasopressin levels were not linked to worse results....
Read the whole story at Scientific American