The "kissing hormone" was tested on volunteers

Scientists have increased the activity of the "love" parts of the brain by injection

Kristina Ulasovich, N+1

Injection of kisspeptin increases the activity of the "love" parts of the brain in response to sexual stimuli, according to scientists from Imperial College in London (Hormone can enhance brain activity associated with love and sex). In the future, this discovery may be used to treat people with psychosexual disorders. The researchers' work was published in the Journal of Clinical Investigation (Comninos et al., Kisspeptin modulates sexual and emotional brain processing in humans).

The protein kisspeptin, which is encoded by the KISS-1 gene, was discovered by scientists in 1996. Initially, researchers considered it as a suppressor of the growth of metastases in melanoma and breast cancer, but later it turned out that it plays an important role in "starting" the process of puberty and further regulates the work of the human reproductive system. Kisspeptin stimulates the work of hypothalamic cells that produce the releasing hormone gonadoliberin. It, in turn, affects the production of luteinizing and follicle-stimulating hormones that regulate the work of the sex glands and the process of maturation of germ cells.

Expression of the KISS-1 gene and its related receptor (encoded by KISS1R) may occur not only in the hypothalamus. Studies show that in rodents and humans, the expression of KISS-1/KISS1R can be produced in other limbic structures of the brain, but nothing is known about the role of kisspeptin in these areas. At the same time, the limbic system plays an important role in the formation of emotions and regulation of reproductive behavior.

The authors of the new work suggested that kisspeptin can control the activity of limbic structures of the brain in response to sexual and emotional stimuli. To test this hypothesis, scientists conducted a double-blind study in which 29 healthy men took part. The volunteers received either an intravenous injection of kisspeptin or a placebo injection, and then were placed in an MRI scanner. While in the device, the subjects viewed images that were supposed to cause them an emotional reaction. These could be photos of happy couples, erotic, neutral or negative scenes, as well as faces with a happy, scared or calm expression.

The graph shows the BOLD response for different brain regions in subjects who received placebo (gray) and kisspeptin (red). Drawing from the Journal of Clinical Investigation

Magnetic resonance imaging showed that kisspeptin increased the response of the limbic structures of the brain in response to erotic images and photos of happy couples. In particular, increased activity was observed in areas associated with sexual arousal and romantic experiences – in the anterior and posterior cingulate gyrus, as well as the left amygdala. When viewing non-sexual images, a similar effect was not observed.

The volunteers also additionally took a survey that examines a person's attitude to sex and sexual arousal from both a psychological and a physiological point of view. The test showed that the more kisspeptin increased the activity of some limbic structures, the less aversion the subjects experienced to sex. It is worth noting that "disgust" is only one of the variables of the questionnaire, which does not at all imply that all volunteers initially suffered from a psychosexual disorder and felt aversion to sex

Thus, the work of scientists shows that kisspeptin can play a role in stimulating emotions and reactions that cause people to have sex and reproduce. However, the study is only at the initial stage: in the future, scientists plan to analyze the effects caused by kisspeptin on a larger group of people, which will include not only men, but also women. Neurophysiologists are especially interested in whether this protein can help with psychosexual disorders and problems associated with conceiving a child.

Previously, kisspeptin was proposed to be used for the treatment of infertility, as well as for ovarian stimulation before the in vitro fertilization procedure. Clinical trials of the past years have shown that injections of kisspeptin can really help women give birth to a healthy baby, but research on its effectiveness is still ongoing.

Portal "Eternal youth" http://vechnayamolodost.ru  25.01.2017