THIS HORMONE IS PROLACTIN AND MAY HELP US SEEING AS SOME HAVE PROBLEMS WITH THIS Pregnancy hormone may bring MS cure Repairs damage in mice: Results 'blew us out of the water': Calgary researcher It is a curious fact that women with multiple sclerosis often go into remission when they are pregnant. A new Canadian study may have determined why, and in the process opened the door to a potential breakthrough treatment of the devastating neurological condition. Researchers at the University of Calgary discovered that a hormone produced during pregnancy to trigger milk production rebuilds myelin -- the crucial protective coating of the brain, the disintegration of which brings on MS. It is possible the hormone, called prolactin, could be given to patients someday to combat the disease, which affects up to 75,000 Canadians, they say. The discovery also holds out hope for treating other neurological conditions caused in part by deterioration of myelin on the brain and spinal cord, such as stroke, spinal cord injuries and some dementia, says the Calgary research team. A hormone produced during pregnancy could lead to an MS treatment. Getty Images Email to a friend Printer friendly Font: ****When prolactin was injected in non-pregnant mice and the researchers used electron microscopes to examine the results, they were taken aback by how much damaged myelin had been repaired. "It blew us out of the water," said Dr. Samuel Weiss, one of the lead authors. The findings of Dr. Weis and Dr. Wee Yong were published today in the Journal of Neuroscience. "Right now there is nothing else that can stimulate myelin repair.... The potential is very significant." The scientists still have to show that prolactin can work similar wonders on human brains, however, and, if so, whether that repair will translate into a treatment for the disease. Dr. William McIlroy, a clinical neurologist at the University of Toronto and medical advisor to the Multiple Sclerosis Society, said the research is "very significant," offering more evidence that it is possible to repair damage to the central nervous system, something that was thought impossible until recent years. But he cautioned that no one should expect miracle cures of MS any time soon. "It's mice, not human beings. Multiple sclerosis is a human disease. It's a big jump from the animal work to the possible human benefits," he said. "Other things have looked promising in animals but have not panned out in humans." Canada has one of the world's highest rates of MS, a disease that can cause blurred vision, extreme fatigue, co-ordination problems and even paralysis. For reasons not entirely understood, the disorder attacks the myelin coating, causing inflammation and eventually disrupting the normal flow of impulses along nerve fibres. It has long been known that pregnant women often experience a respite from MS, but the prevailing theory is that the improvement is a result of immune system changes. The Calgary team had different ideas, noting that prolactin is credited for boosting cell production in the brain and pancreas during pregnancy and that more of it is transported into the brain of expectant mothers. The hormone's main purpose is to help in the development of the fetus and, later, in lactation. The first phase of their research, partly funded by the Multiple Sclerosis Society, found that production of oligodendrocytes, the cells that build myelin, increased in pregnant mice, as did the number of nerve fibres coated with myelin.