Significance of the nicotinic alpha7 receptor in cognition and antipsychotic-like behavior in the rat.

Schizophrenic (SCH) patients show cognitive impairment in attentional performance. Positive allosteric modulators (PAMs) of α7 nicotinic acetylcholine receptors (nAChRs) such as the Alzheimer's drug galantamine (GAL) and PAM-2 are documented to have pro-cognitive properties. However, it is not well established if these properties would be lost, or may hamper antipsychotic efficacy, when given as an adjunct to an antipsychotic which is needed for managing psychotic symptoms.

Preclinical profile of ITI-214, an inhibitor of phosphodiesterase 1, for enhancement of memory performance in rats.

Rationale: Therapeutic agents for memory enhancement in psychiatric disorders, such as schizophrenia, are urgently needed.

Objective: The aim of this study is to characterize the preclinical profile of ITI-214, a potent inhibitor of phosphodiesterase 1 (PDE1).

Methods: ITI-214 was assayed for inhibition of PDE1 versus other PDE enzyme families using recombinant human PDE enzymes and for off-target binding to 70 substrates (General SEP II diversity panel; Caliper Life Sciences).

Effects of adjunct galantamine to risperidone, or haloperidol, in animal models of antipsychotic activity and extrapyramidal side-effect liability: involvement of the cholinergic muscarinic receptor.

The acetylcholine esterase inhibitor/cholinergic nicotinic receptor (nAChR) allosteric modulator galantamine (Gal) is used against cognitive impairment in Alzheimer's disease. Negative/cognitive and psychotic symptom improvement in schizophrenia by adjunct Gal to antipsychotic drugs (APDs) has been reported. Cognitive symptoms in schizophrenia may involve brain prefrontal hypo-dopaminergia.

Conditioned avoidance response in the development of new antipsychotics.

Schizophrenia presents with positive/psychotic, negative and cognitive symptoms. Positive symptoms seems due to a dopamine mesolimbic overreactivity, while negative/cognitive symptoms may conversely be due to mesocortical hypo-dopaminergia. Traditional dopamine D2 receptor blocking antipsychotics (e.