Social isolation does not alter brain regional benzodiazepine binding site numbers, affinity and coupling in the rat

Male Sprague-Dawley rats were differentially housed for 21 days immediately after weaning. Isolated animals showed a selective suppression of exploration of the light side of a two compartment box; spending significantly less time in the light, and making fewer transitions between the light and dark compartments compared to socially reared controls. However, both basal and GABA-stimulated [3H] flunitrazepam binding was unaltered in the frontal cortex, hippocampus, amygdala and cerebellum following social isolation. These results are discussed in relation to other studies on central benzodiazepine receptor changes following a variety of experimental stressors.