NEW ORLEANS -- Some women who become glucose intolerant late in pregnancy may develop gestational diabetes and give birth to larger than normal babies with a tendency to become obese. Now a new study of genetically normal rats indicates that the effect of overfeeding extends for at least three generations and may explain health trends beginning to be seen in human populations in the American Southwest, Japan, Australia and some Pacific islands.
The fact that the overfed animals were genetically normal is important because it shows that conditions during development can have consequences several generations later, even in the absence of genetic abnormalities, emphasized a University of Washington researcher reporting on new work here today at the Society for Neuroscience's annual meeting.
The newborn rats were overfed to duplicate nutritional conditions during late human pregnancy that often affect the babies of diabetic mothers, according to Elsie Taylor, a recent Ph.D. graduate in psychology and UW researcher. Gestational diabetes occurs in 2 to 3 percent of otherwise normal human pregnancies. A mother's system regulates the amount of nutrients fed to her developing baby through the bloodstream, but pregnancy can produce a stress on the pancreas. When this happens, the pancreas sometimes can't produce enough insulin, a hormone that allows the body to use carbohydrates, triggering gestational diabetes.
Taylor says newborn rats are immature at birth so their first three weeks of life correspond to that of a human fetus in the final trimester before birth in terms of metabolic and brain development.
"Newborn rats are God's gift to developmental science," says Jaime Diaz,
a UW psychology professor and Taylor's collaborator on the study. "We can study
a newborn rat and learn much about maturational events which occur during late
human pregn
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Contact: Joel Schwarz
joels@u.washington.edu
206-543-2580
University of Washington
28-Oct-1997