Glutamate decarboxylase activity in brain regions of differentially-housed mice; a difference in the olfactory bulb

Glutamate decarboxylase (GAD) activities were determined in homogenates of 8 brain regions of mice that had been differentially housed ("isolated" vs "grouped") for 4--9 weeks. GAD activity was lower in whole forebrains and in olfactory bulbs of isolated mice, changes which might be associated with their increased aggressiveness.