Featured Research

from universities, journals, and other organizations

Brain's Receptors Sensitive To Pot May 'Open Door' In Treating Drug Dependence, Brain Disorders

Date:
June 7, 2006
Source:
Society of Nuclear Medicine
Summary:
A team of Johns Hopkins researchers developed a new radiotracer -- a radioactive substance that can be traced in the body -- to visualize and quantify the brain's cannabinoid receptors by positron emission tomography (PET), opening a door to the development of new medications to treat drug dependence, obesity, depression, schizophrenia, Parkinson's disease and Tourette syndrome.

A team of Johns Hopkins researchers developed a new radiotracer—a radioactive substance that can be traced in the body—to visualize and quantify the brain’s cannabinoid receptors by positron emission tomography (PET), opening a door to the development of new medications to treat drug dependence, obesity, depression, schizophrenia, Parkinson’s disease and Tourette syndrome.

Discovery of the [11C]JHU75528 radioligand, a radioactive biochemical substance that is used to study the receptor systems of the brain, “opens an avenue for noninvasive study of central cannabinoid (CB1) receptors in the human and animal brain,” explained Andrew Horti, assistant professor of radiology at Johns Hopkins Medicine, Baltimore, Md. He explained that there is evidence that CB1 receptors play an essential role in many disorders including schizophrenia, depression and motor function disorders. “Quantitative imaging of the central CB1 using PET could provide a great opportunity for the development of cannabinergic medications and for studying the role of CB1 in these disorders,” added the co-author of “PET Imaging of Cerebral Cannabinoid CB1 Receptors with [11C]JHU75528.”

Cannabinoid receptors are proteins on the surface of brain cells; they are most dense in brain regions involved with thinking and memory, attention and control of movement. The effects of tetrahydrocannabinol (THC), the primary psychoactive compound in marijuana, are due to its binding to specific cannabinoid receptors located on the surface of brain cells. “Blocking CB1 receptors presents the possibility of developing new, emerging medications for treatment of obesity and drug dependence including alcoholism, tobacco and marijuana smoking,” said Horti.

The usefulness of in vivo (in the body) radioligands for studying cerebral receptors by PET depends on the image quality, and a good PET radiotracer must display a high level of specific receptor binding and low non-specific binding (binding with other proteins, cell membranes, etc.), said Horti. “If the non-specific binding is too high and specific binding is too low, the PET images become too ‘noisy’ for quantitative measurements,” he noted. “We developed a PET radiotracer with a unique combination of good CB1 binding affinity and relatively low non-specific binding in mice and baboon brains,” he added. “Previously developed PET radioligands for imaging of CB1 receptors were not suitable for quantitative imaging due to the high level of image ‘noise,’” he added.

“Even though PET methodology was developed 30 years ago, its application for studying cerebral receptors is limited due to the lack of suitable radioligands,” said Horti. “Development of [11C]JHU75528 will allow noninvasive research of CB1 receptor,” he added, indicating that Johns Hopkins researchers need to complete various safety studies and obtain Food and Drug Administration approval before [11C]JHU75528 can be used for PET imaging in people.

“This discovery would not have been possible without involvement of many highly qualified researchers, including the teams of Robert Dannals and Dean Wong and support of Richard Wahl, director of the nuclear medicine department,” said Horti.

Abstract: A.G. Horti, H. Fan, H.T. Ravert, J. Hilton, A. Kumar, M. Alexander, A. Rahmim, H. Kuwabara, D.F. Wong and R.F. Dannals; Radiology, Johns Hopkins Medicine, Baltimore, Md., “PET Imaging of Cerebral Cannabinoid CB1 Receptors With [11C]JHU75528, SNM’s 53rd Annual Meeting June 3–7, Scientific Paper 387.


Story Source:

The above story is based on materials provided by Society of Nuclear Medicine. Note: Materials may be edited for content and length.


Cite This Page:

Society of Nuclear Medicine. "Brain's Receptors Sensitive To Pot May 'Open Door' In Treating Drug Dependence, Brain Disorders." ScienceDaily. ScienceDaily, 7 June 2006. <www.sciencedaily.com/releases/2006/06/060607082641.htm>.
Society of Nuclear Medicine. (2006, June 7). Brain's Receptors Sensitive To Pot May 'Open Door' In Treating Drug Dependence, Brain Disorders. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2006/06/060607082641.htm
Society of Nuclear Medicine. "Brain's Receptors Sensitive To Pot May 'Open Door' In Treating Drug Dependence, Brain Disorders." ScienceDaily. www.sciencedaily.com/releases/2006/06/060607082641.htm (accessed October 21, 2014).

Share This



More Health & Medicine News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

CDC Revamps Ebola Guidelines After Criticism

CDC Revamps Ebola Guidelines After Criticism

Newsy (Oct. 21, 2014) The Centers for Disease Control and Prevention have issued new protocols for healthcare workers interacting with Ebola patients. Video provided by Newsy
Powered by NewsLook.com
WHO: Ebola Vaccine Trials to Start a in January

WHO: Ebola Vaccine Trials to Start a in January

AP (Oct. 21, 2014) Tens of thousands of doses of experimental Ebola vaccines could be available for "real-world" testing in West Africa as soon as January as long as they are deemed safe in soon to start trials, the World Health Organization said Tuesday. (Oct. 21) Video provided by AP
Powered by NewsLook.com
First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

Newsy (Oct. 21, 2014) A medical team has for the first time given a man the ability to walk again after transplanting cells from his brain onto his severed spinal cord. Video provided by Newsy
Powered by NewsLook.com
CDC Issues New Ebola Guidelines for Health Workers

CDC Issues New Ebola Guidelines for Health Workers

Reuters - US Online Video (Oct. 21, 2014) The U.S. Centers for Disease Control and Prevention has set up new guidelines for health workers taking care of patients infected with Ebola. Linda So reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins