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  • Neurons in the brain change shape when stressed | Newswire
    that play an important role in memory and dictate the strength of neuronal connection Two research associates in Strickland s lab Robert Pawlak and Jerry Melchor placed unstressed mice in a water maze a test designed to assess how well they could locate a hidden platform and how long it took them to learn and remember its location They then compared their performance to mice in which they had induced chronic stress by subjecting them to six hours of restricted motion every day for three weeks They found that the stressed mice were much slower to learn where the platform was located but once they had figured it out they were just as good at remembering the location as the unstressed mice Stress fuzzes your brain because it slows down the cognitive process the animal still gets to the same point if you train it long enough but it s slower McEwen says In order to assess whether tPA is required for a stress reponse the researchers then repeated the experiment using mice bred to lack tPA and found no difference in learning speed between the stressed and unstressed tPA deficient mice The results suggest that tPA somehow prevents damage to hippocampal neurons during times of stress and an examination of the neurons performed in collaboration with their colleagues in India bore this out Normal mice experienced a decrease in dendritic spines and NMDA receptors when they were stressed while tPA deficient rodents showed no change at all And after ten stress free days the normal mice had already partially recovered This is consistent with our previous work that the effects of stress are reversible McEwen says Everything we ve found out about stress and the hippocampus is that the effects are largely reversible if you terminate the stress Strickland

    Original URL path: http://newswire.rockefeller.edu/2005/12/13/neurons-in-the-brain-change-shape-when-stressed/ (2016-02-13)
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  • Single stressful events bring about gradual change in brain structure | Newswire
    it cannot move freely also causes a structural change in the brain not immediately but over days along with higher levels of anxiety These results may help scientists understand what is happening in the human brain during post traumatic stress disorder and other anxiety disorders and depressive illness In earlier studies McEwen and colleagues had looked at changes in the hippocampus and the prefrontal cortex areas of the brain that respond to repeated confinement stress and which are important in memory storage and retrieval Turning to a different area of the brain called the amygdala which is thought to play a role in fear and anxiety memories they wanted to see if it too was involved in processing stressful experiences Indeed they found that repeated stress increased anxiety as well as a form of aggression Understanding how the whole nervous system functions how the different areas of the brain interact is vital to understanding the neurological basis of depressive illness and anxiety disorders says McEwen who is the Alfred E Mirsky Professor and head of the Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology at Rockefeller And we knew of some evidence that the neurons in the amygdala are more active in depression and anxiety disorders The new paper conducted in collaboration with Dr Sumantra Chattarji s laboratory in Bangalore India and MIT shows that even a single stressful event in these animals can have a measurable and delayed influence on the architecture of their brains and on their behavior adds McEwen We would like to think that these findings might become relevant in understanding conditions like post traumatic stress disorder and depression The follow up of this paper is under investigation in collaborative studies with investigators at the Weill Medical College of Cornell University Mt Sinai School of Medicine

    Original URL path: http://newswire.rockefeller.edu/2005/07/28/single-stressful-events-bring-about-gradual-change-in-brain-structure/ (2016-02-13)
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  • “Stressed out” by living and working in NYC? | Newswire
    such beneficial situations stress perception by the brain serves as an early warning signal to the immune system Stress hormones also acutely can improve memory for important experiences and enhance the body s ability to mobilize energy resources Mann says that the impact of stress medically includes both direct and indirect effects Direct effects of stress are emotional distress and somatic symptoms tension headaches insomnia overeating while indirect effects result from overeating and increased smoking and drinking of alcoholic beverages Are there direct effects of stress that cause medical conditions he says Will stress trigger or worsen heart attacks high blood pressure or inflammatory bowel disease Mann who will answer these questions at the Rockefeller event adds that people respond to stress both consciously and unconsciously It s not necessary for us to realize that we are stressed out for the stress to affect us negatively The stress that we don t consciously realize can hurt us he says There can be serious medical consequences such as hypertension and possibly chronic fatigue fibromyalgia and chronic insomnia But while stress has impact on health can it cause cancer This is the era of stress causing everything in the world It s very unfortunate says Cassileth There certainly is a mind body link but I don t think the mind causes cancer and I don t think the mind can cure it Since stress is a normal part of life particularly in New York City what is the best way to cope with it According to Cassileth during a lifetime of reacting to stressful situations we develop both automatic and intentional means of reacting to difficulties Common and usually helpful reactions include temporary denial connecting spiritually or with loved ones and reaching out to others in need Cassileth says Probably universally beneficial are managing uncertainly by imposing structure and interacting with others Among the therapies that Cassileth has found beneficial for relieving the stress that people with cancer and their families often experience are massage therapies music therapy meditation and other relaxation techniques acupuncture and hypnosis She also counsels patients about herbal remedies and food supplements Stress Cassileth says is dangerous when it is extreme and unmitigating but it is very much a part of existence not only in New York but everywhere To understand stress from that perspective and not worry about it unless it persists that in itself is helpful she says About the panelists Bruce S McEwen Ph D is the Alfred E Mirsky Professor and head of the Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology at The Rockefeller University McEwen s laboratory combines molecular anatomical pharmacological physiological and behavioral methodologies and relates its findings to human clinical information As a member of the MacArthur Foundation Research Network on Socioeconomic Status and Health he helps to reformulate concepts and measurements related to stress and stress hormones in the context of human societies He is the co author of a new book with science writer Elizabeth Lasley called The

    Original URL path: http://newswire.rockefeller.edu/2003/04/21/stressed-out-by-living-in-nyc/ (2016-02-13)
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  • More Studies Shed Light on How Prozac Works | Newswire
    brain cell releases serotonin into what is called the synapse This is the space between the axons of the sending nerve cell and dendrites of the receiving nerve cell When serotonin reaches the surface of the dendrite it stimulates or activates receptors that can interact only with this chemical messenger Stimulation of these receptors generates an electrical impulse in the receiving cell that allows brain cells to communicate with each other The serotonin is removed and recycled through a molecule on the sending cell that is called a serotonin re uptake pump By blocking the action of the serotonin re uptake pump Prozac increases the amount of active serotonin that can be delivered to the dendrite Scientists theorize that increased serotonin in the brain somehow helps restore normal message transmission among brain cells and thereby relieves symptoms of depression Serotonin is one of many neurotransmitters Another chemical messenger dopamine affects brain processes that control movement emotional response and ability to experience pleasure and pain Abnormalities in dopamine signaling are associated with Parkinson s disease schizophrenia attention deficit hyperactivity disorder and substance abuse Because dopamine plays a role in these and other neurological and psychiatric disorders Greengard and his research colleagues at Rockefeller University reasoned that this neurotransmitter may interact in some way with serotonin and thus regulate emotional behavior To probe this possible connection the Rockefeller scientists turned to Prozac They observed the effects of the drug in mice genetically altered to lack a protein called DARPP 32 the mouse is called a DARPP 32 knockout mouse Previous research by Greengard and his colleagues has shown that DARPP 32 is a major player in the mechanisms by which the neurotransmitter dopamine produces its effects in the brain The scientists found that the behavioral antidepressive effect and several other biochemical effects of Prozac were abolished when Prozac was administered to the DARPP 32 knockout mice These results show for the first time an important role for DARPP 32 in mediating the actions of serotonin in mice says Per Svenningsson Ph D first author of the scientific papers Moreover the data provide the outline of a molecular mechanism for the behavioral actions of psychostimulants and antidepressant agents that achieve their effects through perturbation of transmission of serotonin In the second PNAS paper Svenningsson Greengard and their colleagues mimicked the effects of Prozac observed in the DARPP 32 knockout mice in a test tube by applying serotonin to brain slices The Rockefeller University scientists discovered that Prozac and serotonin regulate protein phosphorylation at three distinct sites on DARPP 32 Proteins are activated through phosphorylation the process by which a phosphate molecule is attached to a target protein A phosphorylated protein through one or more biochemical steps produces the physiological response characteristic of neurotransmitters Interestingly serotonin increases DARPP 32 phosphorylation at two sites while decreasing phosphorylation at a third site The researchers identified three serotonin receptors responsible for the changes in phosphorylation of DARPP 32 The three receptors work synergistically through DARPP 32 to

    Original URL path: http://newswire.rockefeller.edu/2002/03/04/more-studies-shed-light-on-how-prozac-works/ (2016-02-13)
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  • Prozac | Newswire
    Ph D and other Rockefeller University scientists have illuminated in laboratory mice new details of the complex chemical interaction in the brain that is generated by Prozac the widely prescribed drug for depression More Tags depression Paul Greengard Prozac Stress Search for Categories Science News Awards and Honors Campus News Grants Gifts Topics Video Archive 2015 2014 2013 2012 2011 more About Contact Follow rockefelleruniv Like The Rockefeller University RU

    Original URL path: http://newswire.rockefeller.edu/tag/prozac/ (2016-02-13)
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  • A Little Stress May Have Big Benefits for Health | Newswire
    theorizing that leukocytes dispatched here may increase immune surveillance and enhance immunity They used a model for immune reactions called delayed type hypersensitivity DTH DTH reactions mediate resistance to viral bacterial and fungal infections as well as to certain tumors They also play an important role in ensuring the effectiveness of vaccines To study DTH reactions researchers typically expose the organism to a novel antigen much like a vaccination to establish an immunologic memory The researchers then challenge the organism later with the same antigen to test its memory In the new research Dhabhar and McEwen manipulated the amount of stress hormones in the rats varying the concentrations of hormones in the animals to mimic acute and chronic stress They showed that acute stress or hormonal conditions which mimic acute stress enhanced skin immunity while chronic stress or hormonal conditions which mimic chronic stress suppressed skin immunity They also showed that in contrast to the natural hormones produced by the body dexamethasone a commonly used synthetic version of corticosterone is a potent suppressor of skin immunity This finding was in agreement with the well known use of dexamethasone as an anti inflammatory steroid The scientists also propose a model for the stress response in skin in which stress hormones and immune cells work in concert to promote enhancement of skin immunity Stress hormoneS according to their model may direct the soldiers of the body s immune system the leukocytes to take position at potential battle stations in various organs of the body Calling the stress response a hormonal alarm Dhabhar and McEwen think that acute stress may prepare the immune system for potential challenges such as wounding or infection In contrast chronic stress may suppress immune function decrease leukocyte redistribution and inhibit the function of certain immune cells Dhabhar and McEwen s research may have direct consequences for how doctors treat diseases Because not all aspects of immunity are beneficial to the body for example autoimmunity or an allergic reaction acute stress hormones can actually make those conditions worse One of the paradoxes of stress and immunity is that on the one hand stress is thought to suppress immunity and decrease resisitance to infections and cancer while on the other it is known to exacerbate autoimmune diseases which should be ameliorated by a suppression of immune function This research begins to provide some common basis for explaining some of these paradoxes says McEwen If it s a good immune response like fighting a pathogen or cancer cell then this acute response protects the body in the short run If the immune response is dysregulated for example during allergy asthma or arthritis acute stress may make it worse McEwen points out that the irony of allergies autoimmunity and asthma is that very frequently they are treated with stress hormones If administered properly for example locally in high doses or using synthetic steroids like dexamethasone these hormones mimic the effects of chronic stress and suppress immune function This work provides some basis

    Original URL path: http://newswire.rockefeller.edu/1999/02/06/a-little-stress-may-have-big-benefits-for-health/ (2016-02-13)
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  • DTH | Newswire
    to stress The findings reportedin the Feb 2 issue of the Proceedings of the National Academyof Sciences PNAS contradict the widely held notion thatall stress is bad for health and provides a basis for understandingthe role of stress in health and disease More Tags Bruce S McEwen DTH leukocytes Stress Search for Categories Science News Awards and Honors Campus News Grants Gifts Topics Video Archive 2015 2014 2013 2012 2011

    Original URL path: http://newswire.rockefeller.edu/tag/dth/ (2016-02-13)
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  • From the Center for the Advancement of Health: Stress: It’s Not Just All in Your Head | Newswire
    All in Your Head January 14 1998 Science News Please refer to the following link http www cfah org Tags Stress newswire rockefeller edu Contact Joseph Bonner 212 327 8998 Chemistry Magazine Names Rockefeller Nobel Laureate One of 75 Top Chemists Rockefeller University Creates Center for Immune Disease Research Comments are closed Search for Categories Science News Awards and Honors Campus News Grants Gifts Topics Video Archive 2015 2014 2013

    Original URL path: http://newswire.rockefeller.edu/1998/01/14/from-the-center-for-the-advancement-of-health-stress-its-not-just-all-in-your-head/ (2016-02-13)
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