Navigation Links
Hormone May Play Key Part in Creating Memories

Rise in norepinephrine levels tied to emotionally charged events, study finds

THURSDAY, Oct. 4 (HealthDay News) -- When you experience an emotionally charged event, it's something that is etched into your memory, and now scientists think they know why.

In experiments with mice, researchers found that powerful surges of the hormone norepinephrine -- surges that occur during emotional episodes -- cause a series of events that strengthen the connections between neurons, sealing these events into the memory.

"The question we are addressing is why is it that you can remember some trivial events that occur at a time when there is high emotional arousal," said lead researcher Dr. Roberto Malinow, of the Cold Spring Harbor Laboratory in New York. "For example, everyone remembers where they were when they heard about September 11, even though [they may have been] in some trivial place."

The researchers found that norepinephrine can modify brain cell receptors, making them easier to go into synapses -- the tiny spaces between brain cells -- making it easier to learn and form memories, Malinow said.

In studies with mice, Malinow's group found that norepinephrine, coupled with emotional stress, plays an important role in lowering the threshold for certain brain cell receptors called GluR1. This, in turn, causes a boost in memory, the researchers said.

When the researchers put lab mice through behavioral tests, they found that exposure to norepinephrine made normal mice remember events more clearly. But, mice with mutations of the GluR1 receptors that were exposed to norepinephrine did not show improved memory.

Norepinephrine is known to play a part in the emotional control of memory. During emotional stress, norepinephrine is released by neurons (brain cells) in many areas of the brain, including the hippocampus and the amygdala -- areas involved with forming emotional memories.

The findings are published in the Oct. 5 issue of Cell.

Malinow thinks this finding could lead to new treatments for conditions such as post-traumatic stress disorder.

"It is interesting to find out at the molecular level what emotion is doing," Malinow said. "But there are certain diseases like post-traumatic stress disorder for which we might find targets that have therapeutic benefit. These findings will enhance our knowledge of all diseases that deal with memory."

One expert see this study as an extension of similar work that showed that norepinephrine is involved in the memory of fearful events that can lead to post-traumatic stress disorder.

"In our own work, we have demonstrated that norepinephrine controls the ability of synapses in inputs to the amygdala implicated in cued fear conditioning to undergo long-term potentiation," said Vadim Bolshakov, director of McLean Hospital's Cellular Neurobiology Laboratory, in Belmont, Mass. "This new study complements our work in emphasizing the role of norepinephrine release in the brain in learning and memory mechanisms."

The new research focuses on a different form of learning, Bolshakov said. "The new study nicely demonstrated that norepinephrine enhances a form of learning by facilitating synapses in a region of the hippocampus," he said.

More information

For more on memory, visit the U.S. National Library of Medicine.

SOURCES: Roberto Malinow, M.D., Ph.D., Cold Spring Harbor Laboratory, New York; Vadim Bolshakov, Ph.D., director, Cellular Neurobiology Laboratory, McLean Hospital, Belmont, Mass.; Oct. 5, 2007, Cell

Copyright©2007 ScoutNews,LLC.
All rights reserved

Related medicine news :

1. Thyroid hormone treatment hastens recovery after cardiac surgery
2. Levothyroxine Thyroid Hormone Replacement, Approved for Hypothyroidism
3. Hormone replacement Therapy a headache
4. Ovarian cancer in relationship with Hormone therapy
5. Evaluating The Risks and Benefits of Hormone Therapy
6. Scientists crack mechanism of Leptin-Obesity Hormone
7. Scientists use plant hormones to fight cancer
8. Use parathyroid hormone to fight brittle bone disease
9. Multiple Sclerosis Can Be Treated By Blocking Fat Hormone
10. Hormone contraceptives lead to bone problems
11. Hormone treatment helps obese people slim down
Post Your Comments:
(Date:11/27/2015)... ... 2015 , ... An inventor, from Hopkinsville, Ky., thought there ... home, so he invented the patent-pending ELECTRONIC M.D. , The ELECTRONIC M.D. provides ... so, it could help to prevent potential overdose situations. As a result, it ...
(Date:11/27/2015)... Aliso Viejo, CA (PRWEB) , ... November 27, 2015 , ... ... exclusively for use in Final Cut Pro X. With ProSidebar: Fasion, video editors ... banners, or use ProSidebar as a minimalist title opener. Utilize presets featuring self-animating ...
(Date:11/27/2015)... ... November 27, 2015 , ... A simply groundbreaking television ... an interesting show that delves into an array of issues that are presently affecting ... benefit from open dialogue, this show is changing the subjects consumers focus on, one ...
(Date:11/27/2015)... ... November 27, 2015 , ... The men and ... nonprofit healthcare organizations in the country. They have overseen financial turnarounds, shown commitment ... advance the healthcare industry as a whole through their advocacy and professional efforts. ...
(Date:11/26/2015)... ... November 26, 2015 , ... Patients at Serenity Point ... come together on Thanksgiving Day to share the things that they are most ... Serenity Point YouTube channel, patients displayed what they wrote on index cards, describing ...
Breaking Medicine News(10 mins):
(Date:11/27/2015)... 2015  Lannett Company, Inc. (NYSE: LCI ... acquisition of Kremers Urban Pharmaceuticals Inc. (KU), the ... company UCB S.A. (Euronext: UCB). ... KU from UCB for total consideration of approximately ... customary working capital adjustment, a deduction of certain ...
(Date:11/27/2015)... 26, 2015 ... the "2016 Global Tumor Marker Testing ... and Sales Segment Forecasts, Innovative Technologies, Instrumentation ... to their offering. --> ... "2016 Global Tumor Marker Testing Market: ...
(Date:11/26/2015)... Un nuevo enfoque combina la ... cáncer avanzado.   --> Un nuevo ... Bremachlorin para el cáncer avanzado.   --> ... la terapia fotodinámica de Bremachlorin para el cáncer avanzado. ... --> Clinical Cancer Research . --> ...
Breaking Medicine Technology: