A hormone produced in the pituitary gland may explain why some women are more vulnerable to developing pain than men, potentially paving the way for one day creating individualized pain management plans, a study in female mice has revealed.
Prolactin is an endocrine hormone made in and released from the pituitary gland at the base of the brain. This neurohormone is responsible for many behaviors and physical responses associated with pregnancy and motherhood, such as helping the breasts to grow and make milk during pregnancy. Low levels of prolactin are also found in nonpregnant women and men, according to the US National Library of Medicine.
Researchers studying at the University of Arizona College of Medicine - Tucson also believe that the production of prolactin may also play a role in the body’s pain response. Reporting in Science Translational Medicine, pharmacists CRISPR-edited prolactin producers and receptors to determine the effects on pain response in uninjured female mice. Their work revealed a “sex-dependent mechanism promoting pain” at the level of the nociceptor, the “fundamental building block of pain.”
Women are more known to experience what is called functional pain syndrome (FPS), a poorly understood condition whereby a person will experience pain without any injury. Typically, pain acts as a warning signal to the brain that something is wrong with the body, but those with FPS experience pain without any direct cause or underlying issue. It is believed that between 0.5 to 1.7 percent of the population experiences FPS and for reasons that are unclear, symptoms appear to be more prevalent in women.
"Of all these female-prevalent pain disorders, migraines are among the most common, with about 35 million migraine patients in the United States, and three out of four of those are women. In addition, in fibromyalgia patients, as many as nine out of 10 are women; for irritable bowel syndrome, three out of four are women. When you add up all those women with pain – if you can normalize that – this would provide a huge and important impact on medical care," said Dr Frank Porreca in a statement.
It appears that the prolactin system may also be disrupted by certain drugs, causing more pain than before. When it comes to opioids for pain management, some users – and mostly women – report feeling an increase in pain after taking the drug, a condition known as opioid-induced hyperalgesia.
The findings could pave the way for creating tailored drug therapies that target the prolactin system designed specifically for women at the individual level.