Navigation Links
Schizophrenia mouse model should improve understanding and treatment of the disorder
Date:12/28/2009

AUGUSTA, Ga. Scientists have created what appears to be a schizophrenic mouse by reducing the inhibition of brain cells involved in complex reasoning and decisions about appropriate social behavior.

Findings by Medical College of Georgia scientists, published Dec. 28 in PNAS, elucidate the critical balance between excitation and inhibition of these cells that appears to go awry in schizophrenia. They also provide the first animal model for studying the disabling psychiatric disorder that affects about 1 percent of the population.

"We believe the mouse, which exhibits some of the same aberrant behavior as patients with this disorder, will help identify better therapies," said Dr. Lin Mei, a developmental neurobiologist who directs MCG's Institute of Molecular Medicine and Genetics. "We are doing testing to see if antipsychotic drugs already on the market are effective in treating the mouse."

MCG scientists made the mouse by deleting a candidate gene for schizophrenia, ErbB4, from interneurons, which are brain cells that help shower larger decision-making neurons, called pyramidal cells, with inhibition.

In their earlier work, they identified how ErbB4 and another candidate gene, neuregulin-1, work together to balance the activity of these pyramidal cells. They reported in Neuron in May 2007 that the two help keep a healthy balance between excitation and inhibition by increasing release of GABA, a major inhibitory neurotransmitter in the inhibitory synapses of the brain's prefrontal cortex. Seven years earlier, they showed the two also put a damper on excitatory synapses, communication points between neurons where the neurotransmitter glutamate excites cells to action.

To further test these findings, this time they altered the natural check and balance in cells directly involved with supplying pyramidal neurons with the inhibitor GABA. They did this by knocking out the ErbB4 gene in nearby chandelier and basket interneurons that supply GABA to pyramidal cells. "If we take out ErbB4 in these two interneurons, the neuregulin should have no effect because it can't promote GABA," Dr. Mei, Georgia Research Alliance Eminent Scholar in Neuroscience, said.

His postulation played out in the behavior of the mouse, who exhibited schizophrenia-like behavior including increased movement and impaired short-term memory. The scientists are still gathering data on the manic aspect of schizophrenia in their mice.

For example, both the normal and knockout mice learned they would find a food pellet in each arm of an eight-armed chamber but that if they went to the same arm for seconds, there were none. But the knockouts took longer to learn and finish the task. Knockouts also spent a lot more time sniffing and snooping around and revisiting empty arms.

In another test, knockouts couldn't or wouldn't - make the connection that a relatively low noise would be followed by a slightly louder one. When they treated the knockouts with diazepam, an anti-anxiety medication, they responded similarly to the normal mice: the first sound prepared them for the second.

Dr. Mei suspects that if he could look at the chandelier and basket interneurons in the prefrontal cortex of schizophrenics, he would also find something wrong with their usual role of sensing the need for the inhibitor GABA and supplying it to the pyramidal cells. "In schizophrenia, the baseline of the excitatory neurotransmitter is probably high," he said.


'/>"/>

Contact: Toni Baker
tbaker@mcg.edu
706-721-4421
Medical College of Georgia
Source:Eurekalert  

Related medicine news :

1. APA Comments on FDAs First Approval of Medication to Treat Pediatric Schizophrenia and Bipolar Disorder
2. Normal role for schizophrenia risk gene identified
3. Schizophrenia Gene May Have On/Off Switch
4. Potential new approach to treat cognitive impairments in schizophrenia
5. Schizophrenia candidate genes affect even healthy individuals
6. Hearing messages embedded in noise could be early sign of schizophrenia
7. People with Schizophrenia More Likely to Die of Heart Disease, Reports the Harvard Mental Health Letter
8. US FDA approves ABILIFY for adolescent patients with schizophrenia
9. U.S. Food and Drug Administration Approves ABILIFY(R) (aripiprazole) for Adolescent Patients With Schizophrenia
10. Study Shows Organons Asenapine Demonstrates Efficacy and Tolerability in Treating Acute Schizophrenia
11. Genes Yield More Clues to Schizophrenia
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Schizophrenia mouse model should improve understanding and treatment of the disorder
(Date:1/20/2017)... ... January 20, 2017 , ... Source Vitál Apothecary, a skin and body ... oils, announced the company had a successful visit to the 2017 ECRM Diet, Vitamin ... companies that work in the nutritional, sports and health industries a chance to meet ...
(Date:1/20/2017)... ... January 20, 2017 , ... International Protein, a company based out of Australia ... attended the January ECRM trade show in Hilton Head, SC. , International Protein ... to create a line of products that would elevate her fitness regime. At this ...
(Date:1/20/2017)... ... ... “The Angel”: a heartwarming and earnest tale of faith and believing ... “The Angel” is the creation of published author, Marjorie Lund-Fontaine, a former professional violinist, ... , When asked of her new book, Marjorie says, “‘The Angel’ was written as ...
(Date:1/20/2017)... ... ... “Journey to Christmas:” a beautiful and enchanting tale that teaches children the true meaning of ... three in Oklahoma City, and a devoted woman of faith. , “Becoming a parent ... the back of my mind for years, but actually doing it might have been a ...
(Date:1/19/2017)... , ... January 19, 2017 ... ... the Aerolib Learning Management System: an On-demand E-learning system for Clinical and ... Hospital Administration that is based on Aerolib`s successful education methodology of Disease ...
Breaking Medicine News(10 mins):
(Date:1/20/2017)... , Jan. 20, 2017 Wells Specialty Pharmacy announces ... Howell Branch Rd in Winter Park, Florida ... Park . Operations have been consolidated into the 3796 ... also pleased to announce that Chad Tomlinson , former ... the Company effective immediately. Mr. Tomlinson is a Graduate of ...
(Date:1/20/2017)... 20, 2017 Avillion LLP, a co-developer and ... Mark Weinberg , MD MBA as Chief Medical Officer. Dr Weinberg ... USA . ... Dr Weinberg has spent more than 17 years as a pharmaceutical ... to micro-cap biotech. Over the course of his career, he has ...
(Date:1/19/2017)... Jan. 19, 2017 The global immunomodulators ... by 2025, according to a new study by ... to be predominantly driven by high R&D investments ... large-scale production of new and therapeutically advanced drugs. ... drugs at an unprecedented rate into the immunomodulators ...
Breaking Medicine Technology: