rats 2 7

Tag: "rats" at biology news

The influence of the menstrual cycle on the female brain

...ones (estrogen, progesterone). For example, female rats self-administer cocaine (a drug that acts on the dopamine system) in higher doses after estrogens have been administered to them. The influence of gonadal steroid hormones on the activation of the reward system remained to be studied in humans. A bet...

Scientists discover new species of distinctive cloud-forest rodent

...cially its closest relatives, the bush-tailed tree rats found in South America's lowlands. As a result of the recent discovery, the authors have used The Field Museum's Pritzker Lab for Molecular Systematics and Evolution to resolve the evolutionary relationships among all of these rodents. "The new sp...

Fish can determine their social rank by observation alone, study finds

...ler than Pete. It's been demonstrated in primates, rats and some bird species, but how and why it evolved in animals is a matter of debate." Aggressive bouts In the experiment, the Stanford team used a popular laboratory fish called Astatotilapia burtoni, one of many cichlid species that inhabit ...

Morphine makes lasting -- and surprising -- change in the brain

..., Kauer found that LTP is blocked in the brains of rats given as little as a single dose of morphine. The drug’s impact was powerful: LTP continued to be blocked 24 hours later ?long after the drug was out of the animal’s system. "The persistence of the effect was stunning," Kauer said. "This is your b...

Organic is healthier: Kiwis prove that green is good

...ngin, were extracted from citrus fruits and fed to rats split into groups with some receiving high levels of cholesterol in their diet. Shela Gorinstein of The Hebrew University in Jerusalem found that after 30 days cholesterol levels in rats' blood reduced by around 20-25% in those fed a cholesterol-rich...

Rewarding fat rats

...mean the difference between life and death. When rats and other animals choose the thing that leads to a... In work carried out by Shizgal's team, chubby lab rats were put on a diet to reduce their fat mass and, hence, their leptin levels. They found that restric...

Erectile dysfunction in diabetes is due to selective defect in the brain

... and stretch in diabetic rats. Male Sprague-Dawley rats treated with streptozotocin (STZ) to induce diabet...esponse was also explored. Methodology The rats were exposed to a light/dark cycle, with standard temperature and humidity levels. The animals were ...

Researcher to study astronaut bone loss for space biology agency

...l culture. In the second part, skeletally unloaded rats will be treated with IGF-1 and reloaded on a regular cycle –?much as astronauts might regularly engage in weight-bearing exercise while in orbit –?in order to stimulate integrin production and enhance or recover IGF-1 receptor function. The IGF-1 wil...

3 proteins may play important role in nerve-cell repair

...used nerve cells obtained from the brain tissue of rats and mouse neuroblastoma cells growing in culture to learn more about the three proteins and their involvement in cAMP regulation. The researchers added additional copies of the three genes to the cells to increase the levels of the proteins, and ...

Metacognition: Faced with a test, rats can check their knowledge first

Researchers have found evidence that rats are capable of metacognition—that is, they can pos...hers utilized this approach to study the knowledge rats had of the information they possessed. During the "study phase" of the experiments, rats were presen...

New compound prevents alcoholic behavior, relapse in animals by blocking stress response

... also muted the anxiety that typically develops in rats experiencing the equivalent of a hangover. Such st...(CRF), which is also thought to trigger relapse in rats that have developed a long-term dependency on alcohol. The research, by Markus Heilig, MD, PhD, at t...

Power-boosting signal in muscle declines with age

...K) slows down in the skeletal muscle of 2-year-old rats relative to 3-month-old rats. A chief regulator of...AMPK. They compared AMPK activity in young and old rats following three "perturbations" that normally stimulate the enzyme and, in turn, mitochondria produc...

Glucose triggers brain cell death in rats after hypoglycemic coma

...dents to a model of severe hypoglycemic coma. "The rats could remain hypoglycemic without evidence of sign...ve stress and neuron death were prevented when the rats were given an inhibitor of NADPH oxidase, indicating a key role for this enzyme. "It is well-es...

Hexavalent chromium in drinking water causes cancer in lab animals

...in some drinking water sources. Male and female rats and mice were given four different doses of sodium...rely seen in laboratory animals. Male and female rats had malignant tumors in the oral cavity. The studies conducted in mice found increases in the number...

DNA-damage test could aid drug development

...by industry partners, will be to test the assay in rats and other organisms, and with a wide variety of other toxic chemicals. "This research is the first stage in a new type of clinical drug toxicity test," says Lodish. "And although we haven't done it, you may be able to extend the technique to human...

Molecule that destroys bone also protects it, new research shows

...-17. Other researchers had shown previously, using rats and mice as animal models, that blocking the receptor for IL-17 could be an effective therapy for RA and possibly for other autoimmune diseases such as multiple sclerosis, colitis, psoriasis and lupus. The effects of an IL-17 deficiency in period...

A cherry on top: Tart cherries may alter heart/diabetes factors

...helps the body handle fat and sugar, compared with rats that didn't receive cherries as part of an otherwise similar diet. All of the rats had a predisposition toward high cholesterol and pre-diabetes, but not obesity. All the measures...

Human stem cell treatment restores motor function in paralyzed rats

...generated neurons.” For this study, nine of 16 rats with induced spinal cord ischemia were injected wi...rogressive recovery of ambulatory functions in the rats that received stem cells. Three of the nine rats injected with hSSCs returned to walking at six w...

Common treatment for methamphetamine overdose may damage brain cells

...ethamphetamine toxicity in the same model." The rats in the experiment were injected with either metham...ne solution over a period of eight hours. When the rats were given haloperidol before and nearly halfway through the eight-hour period, Yamamoto and his col...

University of Pittsburgh School of Medicine researchers develop 'off-the-shelf' vascular grafts

...ors then implanted them in the abdominal aortas of rats eight weeks before performing tests to determine how well the grafts had performed. The cell-seeded constructs showed a significantly higher blockage-free rate than unseeded controls (55 percent versus 0 percent). In addition, at eight weeks, there w...

1 2 3 4 5 6 7 8