Wang and Nedergaard found that with a puff of air on a whisker, astrocytes become activated ?pumped with calcium ?in the section of the brain that processes sensory input. The chemical step is a sign that the cell has been triggered in some way and is ready to send out a signal itself. While it's been shown before that astrocytes can become activated under extreme conditions in the laboratory, Nedergaard said this is the first time that such activity has been seen in an organism during everyday circumstances.
"This opens the door to whether these cells are part of everyday higher cognitive functioning that defines who we are as humans," she said.
For years astrocytes have been related to the status of helper to the neurons, which rely on astrocytes to bring nutrients and to clean up after them. While scientists have known that neurons fire electrically in spectacular fashion to send signals, it's only recently that the slower chemical signaling network of the more numerous astrocytes has become widely appreciated by scientists.
Wang's work is the latest in a series of papers by Nedergaard and colleagues scuttling the notion that astrocytes are merely support cells for neurons. More than a decade ago Nedergaard discovered that astrocytes send signals to the neurons, and the neurons respond. S
Source:University of Rochester Medical Center