Posted: 3/16/2007
Johns Hopkins University School of Nursing associate professor Marguerite Littleton-Kearney, PhD, RN, FAAN, has been awarded a five-year $1.25 million grant by the National Institutes of Health (NIH) to continue studying how hormone therapy could potentially reduce the severity of stroke. Her research team will give oral hormone replacement therapy to young and aged rats and examine the effects on the brain’s blood vessels after cerebral ischemia, the restriction of blood flow to the brain.
The grant is a continuation of a previous study, also funded by NIH, in which Littleton-Kearney found that rats receiving estrogen before suffering cerebral ischemia recovered brain blood vessel reactivity better than rats that did not get estrogen. The new funding will allow researchers to examine the effects of both progesterone and estrogen on brain blood flow after cerebral ischemia and attempt to determine the mechanism by which hormones preserve brain blood flow.
“Women are less likely than men to have a stroke during their reproductive years, but after age 65, men and women suffer stroke at about the same rate,” says Littleton-Kearney. “But our understanding of the role of hormones in females during and immediately after stroke has been quite limited.” To simulate the way that humans take hormone replacement therapy, Littleton-Kearney initiated the first study of the effects of estrogen and progesterone on the size of stroke where the animals took the drug orally rather than intravenously or administered under the skin.
She will conduct her research with co-investigator Ray Koehler, PhD, Professor in the Department of Anesthesia Critical Care Medicine, where Littleton-Kearney holds a secondary appointment.