Fast glucocorticoid feedback favors 'the munchies'.

In a recent paper, Tasker and colleagues show that glucocorticoids (GCs) act rapidly, probably through membrane receptors, on corticotropin-releasing factor (CRF)-synthesizing cells to release endocannabinoids. These act locally at presynaptic axons via cannabinoid CB-1 receptors to reduce excitatory glutaminergic input, and therefore induce fast feedback inhibition of CRF by GCs. Similar findings in other hypothalamic neurons suggest that this action of GCs might be common in the brain, and could, in part, explain rapid GC effects on food intake.