By Kimberly Swick Slover
Illustrations by Margaret Reigel
In this issue:Stress-free, Naturally
Until recently much of the research in physiological psychology has focused on the maladies that occur in animals and people. Even as a graduate student, Robert Drugan was more interested in resilience, in learning why some animals cope with stress more effectively than others.
For more than 20 years now, Drugan, an associate professor of psychology, has conducted stress tests on rats, animals whose endocrine systems, which deal with stress, are strikingly similar to those in humans. Surprisingly, he has found that responses to stress vary significantly among rats. "It's remarkable that in animals you see individual differences. People think a rat is a rat is a rat. It's just not true," he explains.
In laboratory tests in which rats were exposed to a variety of moderate stresses, Drugan has found that some "resilient"rats consistently performed behaviors that alleviated or lessened the stress in their environment. Other rats, which he refers to as "vulnerable," failed to act appropriately to control, or cope with, the same stress. Tested again months later, the resilient group performed just as well, while the vulnerable group did as poorly as before. Drugan maintains that this reveals resiliency and vulnerability may be more "a trait than a state."
In trying to discern why the groups differ so radically, Drugan was the first researcher to discover that when under stress, the brains of the resilient animals release a chemical neurosteroid compound similar to tranquilizers. "What my experiment shows is the profound chemical changes in the brain that result from a behavioral treatment. The animals that can cope with stress are dosing themselves with something very much like Valium," he says.
Additionally, because the area of the brain that produces the chemical also affects "emotional" memory, the resilient animals demonstrated poorer recollection of the stressful events. This memory loss, Drugan believes, may further bolster the resilient animals' coping ability.
Pointing to recent breakthroughs in cognitive-behavioral therapy, Drugan suggests exciting potential applications of his own findings. The work of Martin Seligman, a renowned professor at the University of Pennsylvania, shows that through learned changes in behavior, people at risk of depression can deal more effectively with stress. Drugan postulates that since behavioral therapies appear to be able to teach resiliency, it's also possible that the brains of these "changed" individuals begin to naturally emit the Valium-like chemicals that he has detected in resilient rats.
If the human brain does produce natural antidotes to stress, Drugan hopes this could lead to relief for people who suffer from depression, about 20 to 30 percent of whom fail to respond to current drug therapies. They, too, could theoretically be trained through intensive cognitive-behavioral therapy to produce antidotes to their illness, he suggests.
Some individuals will always require drugs to stabilize their condition, and Drugan hopes that one day researchers will be able to develop a better, more effective drug, similar to the chemical produced in rats. "It could be the 'magic bullet' we're looking for," he muses,"a natural antidote with minimal side effects."
Anyone who's ever slogged through a swamp in hot pursuit of a slimy frog can imagine the challenges, and the joys, of capturing 2,000 of them. Wildlife ecologist Kim Babbitt '84, with colleagues from federal and state environmental agencies and 30 volunteers, took on the task last summer for the state's first major study of deformed amphibians. "This is an odd area of research to be in because if you find no problems, there's nothing more to do," says Babbitt, a UNH assistant professor.
Instead, the search at 50 sites in southern New Hampshire yielded a range of deformities in an average of 5 percent of the population, including frogs with missing feet or hind legs, malformed front limbs and eyes missing or deeply sunken in their sockets.
The deformities cause alarm, Babbitt says, because frogs are a "sentinel species" whose thin, permeable skin is highly susceptible to environmental changes. Frogs are also a vital part of the aquatic and terrestrial food chains, preyed on at every stage of development: as eggs, as larvae (tadpoles) and as adults. "I like to say, 'anything that can eat a frog, will eat a frog,'" she jokes.
Yet Babbitt finds something else even more disturbing. "Frogs have been here for millions of years, their skin and eggs exposed to the elements, different environmental pollutants, climate changes," she explains. "They're very sensitive, but they're also very hardy. The fact that they're now being affected is troubling."
The U.S. Environmental Protection Agency (EPA) reports that similar malformations have been found in amphibians around the country, with the heaviest concentrations in the Great Lakes region, followed by the West Coast states and New England. After examining the frogs in New Hampshire, Babbitt is convinced the deformities are developmental rather than the result of injuries. She has been working with Stacia Sower, an internationally known endocrinologist at UNH, comparing the reproductive hormone levels of deformed frogs to those of normal ones, in search of signs of disruptions in the animals' endocrine systems. "Scientists have exposed frogs to (man-made) chemicals in the environment and come up with the same deformities," Babbitt notes.
Babbitt, who specializes in behavioral and community ecology, has formed a team of researchers that includes Sower and two specialists in toxicology and endocrine disruptors from Tufts and the EPA. Over the next three years, the team will try to uncover both the causes and extent of the problem in the region.
"It's a perfect example of a problem that requires a multidisciplinary approach," says Babbitt. "No one scientist is going to be able to solve this."
See the EPA's Web site, http://www.npwrc.usgs.gov/, on amphibian deformities to learn about findings in your area.
Some of the fastest winds on Earth have been recorded on New Hampshire's Mt. Washington, and recently a UNH student researcher found that these fierce winds carry more than just bad weather to the state. Working with the University's Climate Change Research Center (CCRC), Joe Souney '98 conducted a study last winter that suggests these winds also contain chemical "fingerprints" that may help the state identify the sources of pollutants that migrate to New Hampshire from other geographic regions.
As part of his undergraduate research project, Souney and staff and graduate students from the CCRC traveled to the summit for several three- and four-day stays last winter to collect hourly samples of falling snow and ice. The students also compiled daily reports on temperature and wind speed and direction, as well as synoptic weather maps, which track the trajectory of air masses.
"The sampling itself was the most difficult part," says Souney. "We were out there in 80- mph winds. It was very cold, very windy and extremely tiring."
But the pain and the fatigue may have been worthwhile. New England residents have long suspected that air quality in the region is adversely affected by pollutants carried here by the prevailing westerlies, winds traveling west to east from other regions. "The idea was to see if the chemistry of the precipitation reflected changes in the air masses," says Souney. "We were happy to see it did."
By analyzing the snow and ice samples, UNH researchers found that the atmospheric chemistry, or air quality, of Mt. Washington changed significantly with shifts of air masses. Winds from the southwesterly trajectory, for example, resulted in elevated levels of nitrate and sulfate, which likely reflected emissions from coal- and oil-burning power plants and motor vehicles in the Ohio Valley region.
"This tells us that we can use snow and ice as a new tool to fingerprint the chemical identity of these air masses," Souney says, adding that air quality in the region is affected by both local and remote sources. "It should tell us why New England's air quality is changing, and which sources might be responsible for it."
Mark Twickler '85, associate director of the research center, says the work relates closely to the center's mission of developing a climate record for the planet. "We've been doing research all over the globe for over 20 years, and we're applying some of the expertise on a local level," he explains, pointing out that Mt. Washington is an ideal location to measure weather patterns, as three major air masses—Canadian, Midwestern, and Eastern Seaboard—converge there.
The work also helped give a strong sense of direction to Souney's own life. "It was a great hands-on, eye-opening experience," says Souney, who last fall enrolled as a graduate student with the CCRC, specializing in geochemical systems. "I'd been thinking about going on to grad school for awhile, but this experience nailed it down for me."
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