Ricerc@Sapienza

Chronic stress induces maladaptive neural responses in several brain areas including hippocampus. It has been demonstrated that chronic stress exposure induced a downregulation of the putative presynaptic type 2 metabotropic glutamate (mGlu2) receptors, which would reduce the negative feedback role exerted by these receptors. The reduced availability of these receptors would enhance glutamate overflow in the hippocampus, supporting the hypothesis that hippocampal glutamatergic neurotransmission plays a key etiopathological determinant in stress-induced neuropsychiatric disorders.

The serotonin 5-HT2A and glutamate mGlu2 receptors continue to attract particular attention, given their implication in psychosis associated with schizophrenia and the mechanism of action of atypical antipsychotics and a new class of antipsychotics, respectively. A large body of evidence indicates a functional crosstalk between both receptors in the brain, but the underlying mechanisms are not entirely elucidated.

Paradoxical sleep deprivation in rats is considered as an experimental animal model of mania endowed
with face, construct, and pharmacological validity. We induced paradoxical sleep deprivation by placing
rats onto a small platform surrounded by water. This procedure caused the animal to fall in the water at
the onset of REM phase of sleep. Control rats were either placed onto a larger platform (which allowed
them to sleep) or maintained in their home cage. Sleep deprived rats showed a substantial reduction in