Featured Research

from universities, journals, and other organizations

Nicotine Activates More Than Just The Brain's Pleasure Pathways

Date:
January 23, 2009
Source:
Duke University Medical Center
Summary:
Researchers have discovered there are differing taste pathways for nicotine, which could provide a new approach for future smoking-cessation products.

Duke University Medical System researchers have discovered there are differing taste pathways for nicotine, which could provide a new approach for future smoking-cessation products.

"We learned some of nicotine's secrets," said Albino Oliveira-Maia, M.D., Ph.D., a postdoctoral fellow of the Duke Department of Neurobiology. "This is the first study to explore both the peripheral taste pathways activated by nicotine, and how these pathways are integrated in sensory areas of the brain." The peripheral nervous system refers to nerves that are outside of the brain and spinal cord.

Using genetic engineering and measurements of nervous system activity in mice, the researchers found that nicotine sends signals directly to the brain's sensory systems by several pathways, similar to the way taste is perceived.

These findings complement what is known about the effects of nicotine in the dopamine pathway. This is the classic pleasure pathway in the brain, much studied by addiction experts. "Our study in no way contradicts prior findings about nicotine and dopamine," Oliveira-Maia said. "Our findings add to what is known and suggest new approaches for further study."

The findings appeared in the PNAS Early Edition slated for January 19.

"One reason that our findings are interesting is because they relate to previous work that looked at humans with lesions in the insula region of the brain – they had an easier time giving up cigarettes than most people," Oliveira-Maia said. "We found that a part of the insula, the gustatory cortex, has robust responses to nicotine and a capacity to integrate diverse peripheral information to create a unique sensory representation for nicotine."

One taste pathway the Duke researchers uncovered involves nicotinic acetylcholine receptors (nAChR), which scientists previously proposed were taste receptors for nicotine. The researchers found a previously unknown link between these receptors and activity in the taste region of the insula.

They then found a second pathway, the peripheral Trpm5 protein pathway – one that helps animals sense a bitter taste. Mice which had their Trpm5 pathway deleted were unresponsive to several different tastes, including bitterness, but they could still sense the presence of nicotine. "The mice preferred plain water to the nicotine solution, suggesting that there would be a second taste pathway in play, besides the one that had been knocked out," Oliveira-Maia said. The researchers then measured nerve activity in the chorda tympani (CT), which is a branch of the facial nerve that serves the taste buds in the front of the tongue and found that activity in CT nerve fibers increased when nicotine was put on the mice's tongues.

Looking ahead, Oliveira-Maia said that drugs thath block the nAChR receptors are now being used in the treatment of tobacco addiction, mainly because of their effects on the central nervous system, "but it is possible they could also modify the sensory effects of cigarette smoke."

This work was supported by grants from National Institutes of Health, Philip Morris USA, Philip Morris International and a GABBA fellowship from the Portuguese Foundation for Science and Technology.


Story Source:

The above story is based on materials provided by Duke University Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

Duke University Medical Center. "Nicotine Activates More Than Just The Brain's Pleasure Pathways." ScienceDaily. ScienceDaily, 23 January 2009. <www.sciencedaily.com/releases/2009/01/090122152707.htm>.
Duke University Medical Center. (2009, January 23). Nicotine Activates More Than Just The Brain's Pleasure Pathways. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2009/01/090122152707.htm
Duke University Medical Center. "Nicotine Activates More Than Just The Brain's Pleasure Pathways." ScienceDaily. www.sciencedaily.com/releases/2009/01/090122152707.htm (accessed July 29, 2014).

Share This




More Mind & Brain News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Losing Sleep Leaves You Vulnerable To 'False Memories'

Losing Sleep Leaves You Vulnerable To 'False Memories'

Newsy (July 27, 2014) A new study shows sleep deprivation can make it harder for people to remember specific details of an event. Video provided by Newsy
Powered by NewsLook.com
University Quiz Implies Atheists Are Smarter Than Christians

University Quiz Implies Atheists Are Smarter Than Christians

Newsy (July 25, 2014) An online quiz from a required course at Ohio State is making waves for suggesting atheists are inherently smarter than Christians. Video provided by Newsy
Powered by NewsLook.com
Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. 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