Posted by Micki on October 15, 2002, at 20:31:32
In reply to Re: A question for Anxiety Ann » maririp, posted by ZeeZee on October 15, 2002, at 18:58:31
This press release was on a wire service today.
UCLA Neuroscientists Examining Biology of Learning Discover Distinct
Molecular Key to Overcoming FearATTENTION: Medical editorsLOS ANGELES, Oct. 15 (AScribe Newswire) - In a discovery with implications
for treatment of anxiety disorders, UCLA Neuropsychiatric Institute
investigators have identified a distinct molecular process in the brain
involved in overcoming fear. The findings will be published in the Oct. 15
edition of the Journal of Neuroscience.The study of how mice acquire, express and extinguish conditional fear shows
for the first time that L-type voltage-gated calcium channels (LVGCCs) - one
of hundreds of varieties of electrical switches found in brain cells - are
required to overcome fear but play no role in becoming fearful or expressing
fear. The findings suggest that it may be possible to identify the cells,
synapses and molecular pathways specific to extinguishing fear, and to the
treatment of human anxiety disorders.''Brain plasticity, or the ability of the central nervous system to modify
cellular connections, has long been recognized as a key component to
learning and memory,'' said Dr. Mark Barad, the UCLA Neuropsychiatric
Institute's Tennenbaum Family Center faculty scholar and an assistant
professor in-residence of psychiatry at the David Geffen School of Medicine
at UCLA. ''The discovery of a distinct molecular process in overcoming fear
bodes well for development of new drugs that can make psychotherapy, or talk
therapy, easier and more effective in treating anxiety disorders. More
broadly, the findings also suggest that distinct molecular processes may be
involved in the expression and treatment of other psychiatric disorders.''Both the acquisition and extinction of conditional fear are forms of active
learning. The acquisition of conditional fear requires a unique pairing of
an initially neutral conditional stimulus with an aversive unconditional
stimulus. In this research, the conditional stimulus was a tone and the
unconditional stimulus was a mild foot shock.Although extinction, the reduction of conditional responding after repeated
exposures to the conditional stimulus alone, might initially appear to be a
passive decay, or erasure of this association, many studies indicate that
extinction is new inhibitory learning, which leaves the original memory
intact.In examining this process, UCLA researchers used injections of two LVGCC
inhibitors - nifedipine and nimodipine - to test whether LVGCC activity is
required for the 1) acquisition, 2) expression and 3) extinction of
conditional fear. Results showed that blocking LVGCC activity had no effect
on the acquisition or expression of fear, but effectively prevented
extinction.The research was supported by a National Alliance for Research on
Schizophrenia and Depression Young Investigator Award, and by the Forest
Award of the West Coast College of Biological Psychiatry.Other investigators involved in the project were Chris Cain of the UCLA
Interdepartmental Program in Neuroscience and Ashley Blouin of the UCLA
Department of Psychiatry and Biobehavioral Sciences. Barad also is
affiliated with the UCLA Brain Research Institute.The Tennenbaum Family Center at the UCLA Neuropsychiatric Institute was
created earlier this year with a four-year, $1 million gift from Michael E.
and Suzanne Tennenbaum. Michael Tennenbaum is managing member of Tennenbaum
and Company, a private Los Angeles-based investment firm he founded in 1996.In addition to the faculty scholar program, the center is encouraging
research into brain plasticity by providing seed money to promising research
projects and offering graduate student and post-doctoral fellowship support.The UCLA Neuropsychiatric Institute is an interdisciplinary research and
education institute devoted to the understanding of complex human behavior,
including the genetic, biological, behavioral and sociocultural
underpinnings of normal behavior, and the causes and consequences of
neuropsychiatric disorders.Online Resources:- UCLA Neurospychiatric Institute: www.npi.ucla.edu/- UCLA Brain Research Institute: www.bri.ucla.edu/index.htm- David Geffen School of Medicine at UCLA: www.medsch.ucla.edu/- Journal of Neuroscience: www.jneurosci.org/-30-
poster:Micki
thread:109458
URL: http://www.dr-bob.org/babble/20021012/msgs/123823.html