Chronic stress can impair memory

EDINBURGH, Scotland, April 6 (UPI) -- University of Edinburgh researchers say high levels of the stress hormone cortisol in aging mice made them less able to remember how to navigate a maze.

Dr. Joyce Yau of the University of Edinburgh's Centre of Cardiovascular Science and colleagues showed how two receptors in older brains react to the stress hormone cortisol.

The researchers found one receptor was activated by low levels of cortisol, which helped memory, but once

levels of this stress hormone were too high they spilled over onto a second receptor -- contributing to memory impairment.

The researchers are investigating a new chemical compound which blocks an enzyme -- 11beta-HSD1 -- that is involved in producing stress hormones within cells. The compound could be used to develop a drug treatment to slow the normal decline in memory associated with aging or even improve memory in the very old, Yau says.