Category: Anti Drug Movement

[amazon_link asins=’B00T4VACY0,B075HP5189,B00UV549XS,B00X5Y5PBC,B003KGKH04,B008XDNZSK,B001AJ4L1E,B008QPCEDC,0062220845′ template=’ProductCarousel’ store=’finmeacur-20′ marketplace=’US’ link_id=’5c801d73-00c4-11e8-8c04-e987a05740f1′]

Researchers have made a breakthrough in uncovering the mystery behind why teens get hooked on cocaine more easily than adults by finding that developing brains are more powerfully motivated by drug-related cues.

The study found that adolescent rats given cocaine were more likely than adults to prefer the place where they got it.
Epidemiological studies confirm that of people in various age groups who experiment with drugs, teens are by far the most likely to become addicted as they are driven by drug related cues.
During the study psychologists Heather Brenhouse, PhD, and Susan Andersen, from McLean’s Developmental Psychopharmacology Laboratory introduced rats that were 38 or 77 days old which is equivalent to 13 or 20 human years, to an apparatus with one central and two larger side chambers that had different flooring, wall colours and lighting.
The injected the rats with saline solution in the morning for three days in a row and placed them in one side chamber for an hour.
Four hours later, they injected them with a preference-forming dose of cocaine and placed them in the opposite-side chamber for an hour.
To test the “conditioned place preference” for the chamber where they got cocaine, the rats were let free to explore the entire apparatus in a drug-free state for 30 minutes on the 4th day
Brenhouse and Andersen calculated how long each rat spent in the drug-paired side relative to total time spent on either side. They repeated the procedure every 24 hours until each animal’s place preference was extinguished, when the time they spent in the drug-paired chamber was cut in half – suggesting no lingering preference for either side.
Relative to adults, adolescent rats required around 75 percent more trials to extinguish a preference for the place where they were given the drug.
After each rat’s last extinction trial, the researchers waited 24 hours, injected a low 5 mg/kg “priming” dose of cocaine, and put it back in the apparatus to test for place preference.
During this test for “reinstatement” of extinguished preferences, adolescent rats showed a significantly greater renewed preference than did adults for the drug-paired chamber. Those that had originally learned on a 10 mg/kg dose of cocaine showed 40 percent greater reinstatement than the few adult rats that showed a place preference at the lower dose.
Brenhouse and Andersen view this as a sign that adolescents form stronger memories for even less potent rewards.
“Adolescent vulnerability to addiction involves robust memories for drug-associated cues that are difficult to extinguish.”
They believe that this is because their brains are still developing.
The researchers believe that the new findings may help in developing new treatments for youthful addiction.
The study appears in Behavioral Neuroscience, published by the American Psychological Association.

Click to see also:->Women who turn to illegal drugs in their struggle to lose weight

Researchers reverse cocaine effects in mice study

Sources:The Times Of India

[amazon_link asins=’B01LW7WBUY,B01K2GYI04,B00FYZL5E6,B01MY5VT60,B00VVVD4SW,B016NJL3Y8,B000GIPJ16,B06XCTNHN8′ template=’ProductCarousel’ store=’finmeacur-20′ marketplace=’US’ link_id=’83518643-00c7-11e8-a1bb-e9b36ab26e7f’]

Athletes who take human growth hormone may not be getting the boost they expected. While growth hormone adds some muscle, it doesn’t appear to improve strength or exercise capacity, according to a review of studies that tested the hormone in mostly athletic young men.

“It doesn’t look like it helps and there’s a hint of evidence it may worsen athletic performance,” said Dr. Hau Liu, of Santa Clara Valley Medical Center in San Jose, Calif., who was lead author of the review.

Growth hormone, or HGH, is among the performance enhancers baseball stars Roger Clemens and Andy Pettitte were accused of taking in the blockbuster Mitchell Report. Clemens denies using the hormone, while Pettitte admits using it.

But the new research has some limitations and sheds no light on long-term use of HGH. The scientists note their analysis included few studies that measured performance. The tests also probably don’t reflect the dose and frequency practiced by athletes illegally using the hormone. Experiments like that aren’t likely to be conducted.

“It’s dangerous, unethical and it’s never going to be done,” said Dr. Gary I. Wadler, a member of the World Anti-Doping Agency and a spokesman for the American College of Sports Medicine.

Consequently, those in the field have to depend on such reviews or “what we hear on the ground,” he added.

Human growth hormone is made by the pituitary gland and promotes growth. A synthetic version has been available since the 1980s and its use is restricted for certain conditions in children and adults, including short stature, growth hormone deficiency and wasting from AIDS.

Although banned for other uses, growth hormone has been used by a variety of athletes and was cited along with steroids as one of the performance-enhancing drugs abused by baseball players in the report in December by former Senate majority leader George Mitchell. Several athletes, including Pettitte, have said they used HGH while recovering from an injury, an issue not covered in the review.

“There are a lot of claims that it’s this wonder drug,” said Liu.

Wadler said one of the appeals of growth hormone for athletes is that it can’t be detected in a urine test. A blood test will be available soon, and another is in development, he said.

“They think they are getting a free ride — they aren’t getting a drug test,” he said. “They believe they are stronger and bigger.”

Liu and his colleagues at Stanford University sought to find out if growth hormone really could improve performance. They looked for the best published tests, those comparing participants who got the hormone to those who didn’t get the treatment.

They analyzed 27 studies involving 440 participants. The results were released Monday by the Annals of Internal Medicine.

Researchers found that those who got the hormone put on about 5 pounds more of muscle, and lost about 2 pounds more of fat, although the fat loss wasn’t statistically different. The researchers said some of the extra body mass could just be fluid buildup.

There was no difference found in strength or exercise stamina between the two groups, but there were only two strength studies and eight that measured exercise. Those who got the hormone had more side effects including swelling and fatigue.

The review couldn’t consider long-term effects, since the longest study was three months, and most were much shorter.

The researchers also said the doses used in the research may be lower than those used by athletes, who may be combining growth hormone with other performance-enhancing drugs.

Dr. Alan Rogol of the University of Virginia and the Indiana University School of Medicine, said the work was a good review but had to rely on inadequate research.

“There are just tons of things we don’t know,” said Rogol.

The California researchers had support from Stanford, government agencies and Genentech Inc., which makes growth hormone; none of the groups had a role in the study. Two researchers also have been consultants or received grants from Genentech and other drugmakers.

Sources:http://ap.google.com/article/ALeqM5iwSgP7BaY5LPhyRmCu_nVADDyCEgD8VFDR6O0