Key brain circuits that control compulsive drinking in rats identified

London, July 23 (ANI): Scientists have identified circuitry in the brain that drives compulsive drinking in rats.

A research team led by scientists from the Ernest Gallo Clinic and Research Center at the University of California, San Francisco found they could reduce compulsive drinking in rats by inhibiting key neural pathways that run between the prefrontal cortex, which is involved with higher functions such as critical thinking and risk assessment, and the nucleus accumbens, a critical area for reward and motivation.

The authors noted that there are already several FDA-approved medications that target activity in these pathways, thus potentially opening an accelerated track to new treatments for compulsive drinking.

The study was conducted on rats that regularly drank 20 percent alcohol. The rats drank both unmixed alcohol and alcohol mixed with extremely bitter quinine, said senior investigator F. Woodward Hopf, PhD, an assistant adjunct professor of neurology at UCSF.

Hopf explained that this alcohol-quinine solution, which he described as "like a vodka tonic without the sugar," is often used as a rodent model of compulsive drinking, or "drinking in the face of negative consequences." In rats, he said, the negative consequence is the bitter taste, while in humans who drink compulsively, "the negative consequences are profound: people continue to drink despite the potential loss of jobs, marriages, freedom, even their lives."

In the United States, alcoholism is estimated to cost $224 billion per year - almost $2 per drink - mostly from lost productivity and crime, and leads to 100,000 preventable deaths per year.

The drinking rats showed a notable increase in the NMDA receptor (NMDAR), which lead author Taban Seif, PhD, a Gallo Center researcher, called "a molecule that excites the brain." When the rats were injected with an NMDAR blocker, their consumption of quinine-laced alcohol dropped significantly, while regular alcohol use was unaffected. "In other words, only the compulsive drinking was affected," said Seif.

The team then focused its research on connections from two specific regions of the rats' prefrontal cortex where they had discovered the presence of unusual types of NMDARs: the medial prefrontal cortex, which mediates conflict during decision-making, and the insula, which is critical for self-awareness and feelings. "In a non-addict, these brain areas tell you when something is potentially harmful and bad, and to run away as fast as possible," said Hopf. "But if you're a compulsive drinker, it seems instead that they give you a comforting pat on the back, in effect telling you it's OK to have another drink, nothing to worry about."

Using a technique called optogenetics, the scientists inserted halorhodopsin, a light-sensitive protein, into these areas. They then used fiber-optic cables implanted in the rats' brains to send pulses of laser light that activated the halorhodopsin, which in turn inhibited the regions' connections to the nucleus accumbens. The researchers found that rats inhibited in this way drank significantly less quinine-laced alcohol, while their intake of regular alcohol solution remained unaffected.

"The fact that we reduced the rats' compulsive drinking using two different methods - an NMDAR blocker and direct inhibition of connections - tells us that we have probably identified the right areas," said Hopf.

The next logical step for the research team, said Hopf, would be to work with clinical researchers on an NMDAR blocker trial in human subjects.

The study has been published in Nature Neuroscience. (ANI)

Matches

MORE TOP STORIES TODAY

On Now: Kolkata vs Bangalore

On Now: Kolkata vs Bangalore

IPL 7, GAME 11—Bangalore bowl, Murali in, still no Gayle. KKR bring in Umesh, Lynn. More »

Kolkata bowling vs Bangalore batting might

Kolkata bowling vs Bangalore batting might

The likely return of Gayle will boost Bangalore, but the result could be determined by Kolkata's bowlers. More »

Boycotting IPL will not save cricket

Boycotting IPL will not save cricket

Boycotting the IPL as a means of protest against the grime in the game may not yield the desired results. More »

Gambhir a knock away from striking form - KKR coach

Gambhir a knock away from striking form - KKR coach

Gautam made an eight-ball duck in the opening game against Mumbai and in the second game against Delhi, he lasted only half those balls. More »

Rivals say Srini group delaying BCCI special general meeting

Rivals say Srini group delaying BCCI special general meeting

The group opposed to Srinivasan alleged that since BCCI secretary Sanjay Patel belongs to the president’s group, he was intentionally delaying the SGM… More »

April 24: A legend is born

As Sachin Tendulkar turns 41 - here's a look at some offbeat moments from the Master Blaster's innings. More »

Jadeja spins out Rajasthan in close chase

Jadeja spins out Rajasthan in close chase

IPL 7, GAME 10—Chennai beat Rajasthan by 7 runs after last-over scare. More »

Cleaning up the game starts with fans

Cleaning up the game starts with fans

... because, as recent events reveal, the BCCI has little intention of doing it. More »

SL in 'difficult place' after Farbrace exit

SL in 'difficult place' after Farbrace exit

Sri Lanka depart for assignments in Ireland and England in two weeks, and Sanath Jayasuriya suggested Marvan Atapattu would be interim head coach for those… More »

Vithanage, Priyanjan get T20 call-ups

Vithanage, Priyanjan get T20 call-ups

Herath has been rested, while the team will be without the veteran pair of Mahela Jayawardene and Kumar Sangakkara, who retired from T20 internationals… More »

Chandimal axed as T20 captain

Chandimal axed as T20 captain

Sri Lanka's cricket selectors on Wednesday sacked Dinesh Chandimal as Twenty20 captain and replaced him with Lasith Malinga, while Angelo Mathews was… More »

'BCCI should have picked panel with care'

'BCCI should have picked panel with care'

Dalmiya said that it was the first time that the BCCI had been faced with a situation where the apex court had hauled up the Board and it should have acted… More »

Farbrace is England's assistant coach

Farbrace is England's assistant coach

The ECB continued the restructuring of the England coaching set-up on Wednesday by announcing the appointment of Paul Farbrace as assistant coach. More »

SC asks Mudgal committee to continue

SC asks Mudgal committee to continue

Mukul Mudgal has communicated to the court his willingness to take up the investigation and has been asked to specify the terms and modalities on April… More »

Sri Lanka players resolve pay dispute

Sri Lanka players resolve pay dispute

The pay dispute between Sri Lanka Cricket and its 13 contracted players ended on Wednesday when the latter agreed to accept 10 percent of the participation… More »

Hope to be fit for next game - Pietersen

Hope to be fit for next game - Pietersen

With two heavy defeats at the hands of Bangalore and Chennai, Daredevils currently languish near the bottom of the table. More »

'SC decision could hurt BCCI's status'

'SC decision could hurt BCCI's status'

The Supreme Court prefers that the Justice Mudgal panel further investigate the IPL corruption scandal. More »

Mudgal panel drops bombshell in court

Mudgal panel drops bombshell in court

The Mukul Mudgal probe committee dropped a bombshell in the Supreme Court on Tuesday by making a sensational claim that it was forced to stop audio recording… More »

Perfect Punjab trounce Hyderabad

Perfect Punjab trounce Hyderabad

IPL7, GAME 9—Maxwell (95, 43b), Balaji (4-13) set up 72-run win. More »

Have the ECB played an unfair game?

Have the ECB played an unfair game?

Money talks, but it is in light of this ICC shakeup that the ECB's act of soliciting of another team's coach deteriorates from free-market aggression to… More »

Farbrace quits for England post

Farbrace quits for England post

He will assist Peter Moores who was unveiled as the new England coach on Saturday. More »

Moin appointed to manage Pakistan team

Moin appointed to manage Pakistan team

Pakistan on Monday reappointed Moin Khan as chief selector and manager of the national team, a week after fellow former captain Rashid Latif turned down… More »

Chennai smash Delhi for first win

Chennai smash Delhi for first win

IPL7, MATCH 8—Raina-led middle order, superlative catching give CSK a 93-run win. More »

'BCCI reputation lowest in 80 years'

'BCCI reputation lowest in 80 years'

The former BCCI president says he was "disillusioned" by the happenings at the emergent working committee meeting on Sunday. More »