Interestingly, estrogen receptors were still intact and receptive in the uterus, another important target of estrogen. We try to understand why there is a difference in the tissue, says Dr. Brann.They also want to examine the neuroprotective benefits of estrogen made locally in the brain compared to that made by the ovaries, the main source of estrogen. Over the past decade, scientists have discovered that neurons and glial cells in the brain to support the production of estrogen locally via the enzyme aromatase. Men and women have estrogen receptors in the brain and the scientific consensus is that the brains of men also produce estrogen.
Animal studies indicate they may be right, at least in terms of the ability of estrogen to protect the brain. The studies focused on the hippocampus, a center of learning and memory, where scientists have shown that estrogen was strongly risk of stroke in rats that estrogen is one week after the surgical removal of the ovaries. When replacement therapy was delayed for 10 weeks after removal – equivalent to a couple of years of human life – estrogen is essentially useless.
The next steps are to study the status of estrogen receptors in the brains of mice aged of course – the equivalent of about 70 years in humans – to see what happens with normal age-related loss of estrogen, waiting for a moment , then put estrogen back to see if there is any benefit.
Animal studies show a critical period for the replacement of estrogen and when treatment is delayed, estrogen receptors on brain cells are significantly reduced with estrogen neuroprotection broadcasting in general, according to scientists at the Medical College of Georgia, North China Coal Medical University and the University of Texas Health Science Center at San Antonio.
But inside the brain, there were other signs of collateral damage from estrogen deficiency. CA3, an area of the hippocampus, which tends to be resistant to blow, they become vulnerable to stroke in rats that have long term without estrogen. Brann said. NADPH oxidase, the enzyme that makes superoxide free radicals, is found in high levels in the CA1 region in the vicinity, but at low levels of CA3. The two regions, he noted, are essential for learning and memory.
If this is true for humans, using only the surgical menopause as an example, most women are less came to a severe, Dr. Brann, noting that stress could be not only during stress but also serious emotional or simple aging. This is what we think based on these data, said Dr. Brann.
For estrogen replacement to provide protection, is likely to be given soon after the fall of the level or the surgical removal of the ovaries, the scientists report in the Journal of Neuroscience.
The controversy that resulted from optimization of the Women’s Health Initiative, a study of 12 women aged from 50 to 79,161,808, which examined the health benefits of. Among the surprising findings is that estrogen and progesterone and estrogen therapy actually increased the risk of stroke, rather than reduce it. Critics say that a problem with the study was that many women had gone years without hormone replacement.
When a stroke occurs, estrogen helps to suppress free radical production in CA1, which can become lethal to cells at other levels increased.
Studies have shown CA1 and CA3 regions were equally vulnerable to stroke in animals that have long periods without estrogen.