Featured Research

from universities, journals, and other organizations

Marijuana's anxiety relief effects: Receptors found in emotional hub of brain

Date:
March 6, 2014
Source:
Vanderbilt University Medical Center
Summary:
Cannabinoid receptors, through which marijuana exerts its effects, have been found in a key emotional hub in the brain involved in regulating anxiety and the flight-or-fight response. This is the first time cannabinoid receptors have been identified in the central nucleus of the amygdala in a mouse model.

Sachin Patel, M.D., Ph.D., right, Teniel Ramikie, and colleagues found cannabinoid receptors in a part of the brain involved in regulating anxiety.
Credit: Joe Howell

An international group led by Vanderbilt University researchers has found cannabinoid receptors, through which marijuana exerts its effects, in a key emotional hub in the brain involved in regulating anxiety and the flight-or-fight response.

This is the first time cannabinoid receptors have been identified in the central nucleus of the amygdala in a mouse model, they report in the current issue of the journal Neuron.

The discovery may help explain why marijuana users say they take the drug mainly to reduce anxiety, said Sachin Patel, M.D., Ph.D., the paper's senior author and professor of Psychiatry and of Molecular Physiology and Biophysics.

Led by first author Teniel Ramikie, a graduate student in Patel's lab, the researchers also showed for the first time how nerve cells in this part of the brain make and release their own natural "endocannabinoids."

The study "could be highly important for understanding how cannabis exerts its behavioral effects," Patel said. As the legalization of marijuana spreads across the country, more people -- and especially young people whose brains are still developing -- are being exposed to the drug.

Previous studies at Vanderbilt and elsewhere, Patel said, have suggested the following:

  • The natural endocannabinoid system regulates anxiety and the response to stress by dampening excitatory signals that involve the neurotransmitter glutamate.
  • Chronic stress or acute, severe emotional trauma can cause a reduction in both the production of endocannabinoids and the responsiveness of the receptors. Without their "buffering" effect, anxiety goes up.
  • While marijuana's "exogenous" cannabinoids also can reduce anxiety, chronic use of the drug down-regulates the receptors, paradoxically increasing anxiety. This can trigger "a vicious cycle" of increasing marijuana use that in some cases leads to addiction.

In the current study, the researchers used high-affinity antibodies to "label" the cannabinoid receptors so they could be seen using various microscopy techniques, including electron microscopy, which allowed very detailed visualization at individual synapses, or gaps between nerve cells.

"We know where the receptors are, we know their function, we know how these neurons make their own cannabinoids," Patel said. "Now can we see how that system is affected by … stress and chronic (marijuana) use? It might fundamentally change our understanding of cellular communication in the amygdala."


Story Source:

The above story is based on materials provided by Vanderbilt University Medical Center. The original article was written by Bill Snyder. Note: Materials may be edited for content and length.


Journal Reference:

  1. Teniel S. Ramikie, Rita Nyilas, Rebecca J. Bluett, Joyonna C. Gamble-George, Nolan D. Hartley, Ken Mackie, Masahiko Watanabe, István Katona, Sachin Patel. Multiple Mechanistically Distinct Modes of Endocannabinoid Mobilization at Central Amygdala Glutamatergic Synapses. Neuron, 2014; 81 (5): 1111 DOI: 10.1016/j.neuron.2014.01.012

Cite This Page:

Vanderbilt University Medical Center. "Marijuana's anxiety relief effects: Receptors found in emotional hub of brain." ScienceDaily. ScienceDaily, 6 March 2014. <www.sciencedaily.com/releases/2014/03/140306142803.htm>.
Vanderbilt University Medical Center. (2014, March 6). Marijuana's anxiety relief effects: Receptors found in emotional hub of brain. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2014/03/140306142803.htm
Vanderbilt University Medical Center. "Marijuana's anxiety relief effects: Receptors found in emotional hub of brain." ScienceDaily. www.sciencedaily.com/releases/2014/03/140306142803.htm (accessed July 24, 2014).

Share This




More Mind & Brain News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Idaho Boy Helps Brother With Disabilities Complete Triathlon

Idaho Boy Helps Brother With Disabilities Complete Triathlon

Newsy (July 23, 2014) — An 8-year-old boy helped his younger brother, who has a rare genetic condition that's confined him to a wheelchair, finish a triathlon. Video provided by Newsy
Powered by NewsLook.com
Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Newsy (July 22, 2014) — The 83 new genetic markers could open dozens of new avenues for schizophrenia treatment research. Video provided by Newsy
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) — The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Do Obese Women Have 'Food Learning Impairment'?

Do Obese Women Have 'Food Learning Impairment'?

Newsy (July 18, 2014) — Yale researchers tested 135 men and women, and it was only obese women who were deemed to have "impaired associative learning." Video provided by Newsy
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:
from the past week

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