Interactions of serotonin2A and metabotropic glutamate2/3 receptors in behavioural control in rats

Serotonin (5-hydroxytryptamine, 5-HT)2A and metabotropic glutamate (mGlu2/3) receptors show a strikingly overlapping distribution and share strong behavioural and functional interactions. The thesis investigated the functional relevance of 5-HT2A and mGlu2/3 receptor interactions focussing on two aspects of behavioural inhibition: impulsivity and sensorimotor gating mechanisms. Experiments were conducted in Lister Hooded rats trained in different tests for impulsivity and treated with 5-HT2A and mGlu2/3 receptor ligands. Sensorimotor gating mechanisms were assessed via the prepulse inhibition of the acoustic startle reflex. Taken together, the studies show close antagonistic interactions between 5-HT2A and mGlu2/3 receptors at the behavioural and systems level. The results further suggest that mGlu2/3 receptor agonists have the potential to attenuate impulsivity-related disorders and sensorimotor gating deficits resulting from a hyperserotonergic state.