The Role of Serotonin and Dopamine Neurotransmitters in Obsessive-Compulsive Disorder

Therapeutic advances, brain imaging studies, and the results of drug-related research, have led to revising the etiology theories of obsessive-compulsive disorder (OCD) and establishing new research paradigms. OCD is considered as a psychiatric neuropathy with an essential biological nerve abnormality. In this context, the important determinant factor of the human quality of thinking is the processing of information in different neuronal networks. The microenvironment of the brain is important for the efficiency and accuracy of thought. In the present study, the neurochemical properties and the role of various neurotransmitters in OCD are discussed.  Numerous studies have shown that the serotonergic 5-HT2C receptor plays an important role in the pathophysiology of OCD. Furthermore, OCD is associated with changes in the striatal serotonergic system. The density of the serotonergic neurotransmitters markedly increases in the striatum. In addition to serotonin, dopaminergic D3, D2, D1 receptors play a crucial role in the development of OCD. A significant enhancement of dopamine function is observed in the nucleus accumbens and right prefrontal cortex.