A progressive loss of dopamine neurons in the substantia nigra (SN) is considered the main feature of idiopathic Parkinson's disease (PD). Recent neuropathological evidence however suggests that the axons of the nigrostriatal dopaminergic system are the earliest target of α-synuclein accumulation in PD, thus the principal site for vulnerability. Whether this applies to in vivo PD, and also to t...

Schizophrenia is a chronic debilitating mental illness. In many aspects, the neuropathology of schizophrenia closely associated with neuroinflammation, especially microglial activation. Microglial hyperactivity, which characterized by predominant release proinflammatory cytokines serves as basis neuroinflammation hypothesis in schizophrenia. The enhanced inflammatory induce neuronal susceptibil...

Dopamine and opioid neurotransmitter systems share many functions such as regulation of reward and pleasure. μ-Opioid receptors (MOR) modulate the mesolimbic dopamine system in ventral tegmental area and striatum, key areas implicated in reward. We hypothesized that dopamine and opioid receptor availabilities correlate in vivo and that this correlation is altered in obesity, a disease with alte...

To explore the functional consequences of cannabinoid withdrawal in the rat mesolimbic dopamine system, we investigated the anatomical morphology of the mesencephalic, presumed dopaminergic, neurons and their main post-synaptic target in the Nucleus Accumbens. We found that TH-positive neurons shrink and Golgi-stained medium spiny neurons loose dendritic spines in withdrawal rats after chronic ...

In the previous study we reported that morphine-induced conditioned place preference (CPP) could be suppressed by peripheral electric stimulation (PES), an effect related to the increased gene expression of opioid peptides in the central nervous system. Considering that opioids were known to elevate dopamine (DA) activity in the mesolimbic brain, the present study was designed to further analyz...

The hunger hormone, ghrelin, is produced not only in response to food deprivation, but also released during various types of stress. In recent years, the rise ghrelin levels has come be seen as an essential component stress response. review devoted ghrelin-dependent mechanisms providing reciprocal interaction between hypothalamuspituitaryadrenal cortex axis and dopaminergic reward system. Direc...

backgroud: protein-protein interaction, plays a key role in signal transduction in signaling pathways. different approaches are used for prediction of these interactions including experimental and computational approaches. in conventional node-edge protein-protein interaction networks, we can only see which proteins interact but ‘structural networks’ show us how these proteins interact which ca...

Our previous observations show that chronic opiate administration, including self-administration, decrease the soma size of dopamine (DA) neurons in the ventral tegmental area (VTA) of rodents and humans, a morphological change correlated with increased firing rate and reward tolerance. Given that a general hallmark of drugs of abuse is to increase activity of the mesolimbic DA circuit, we soug...

It is well established that learning can occur without external feedback, yet normative reinforcement learning theories have difficulties explaining such instances of learning. Here, we propose that human observers are capable of generating their own feedback signals by monitoring internal decision variables. We investigated this hypothesis in a visual perceptual learning task using fMRI and co...