A team of New Zealand scientists has identified neurological factors that underlie some cases of infertility. The key lies in a group of about 2000 neurons that controls the production of kisspeptin. The hormone stimulates the production of luteinizing hormone, one of the male and female fertility managers.
Professor Allan Herbison, lead author of the study, studied the effects of luteinizing hormone. Both low and high levels always make fertility collapse. This means that the levels must go up and down as needed. A change that is too rapid or absent will damage the delicate mechanisms that control human reproduction.
Professor Dave Grattan is studying another factor that influences luteinizing hormone levels. Placing himself in the wake of Herbison, Grattan analyzed the action of prolactin. It has been known for decades that too high levels of prolactin cause infertility, but the reason was unknown. According to Grattan, too much prolactin could influence the levels of the luteinizing hormone and unpack its delicate balance.
An analysis of the neurons detected by Herbison has proven the presence of prolactin receptors. These receptors are able to activate or deactivate neurons that stimulate the production of luteinizing hormone. In this way they adjust the levels according to need. When they do not work properly, this causes abnormalities even in hormone levels and in fertility.
The two discoveries have influenced each other, although they are different projects. Both could pave the way for possible infertility treatments caused by too high levels of prolactin.