The mesostriatal dopaminergic system, which comprises the mesolimbic and the nigrostriatal pathways, plays a major role in neural processing underlying motor and limbic functions. Multiple reports suggest that these processes are influenced by hemispheric differences in striatal dopamine (DA) levels, DA turnover and its receptor activity. Here, we review studies which measured the concentration...

Dopamine receptors are responsible for diverse effects within and outside the central nervous system. The five dopamine receptors that have been cloned (DIA, D1B also known as D5, D2, D3, and D4) belong to two major families; the D1 like and D2 like dopamine receptors. The D1 like receptors are linked to the stimulation while D2 like receptors are linked to the inhibition of adenylyl cyclase. T...

Ventral tegmental area (VTA) dopaminergic (DAergic) and GABAergic neurons are critically involved in mechanisms of reward, reinforcement and emotional arousal. The hypothalamus regulates the homeostatic drive to eat and sends a massive output to the VTA, including projections from neurons containing orexins, the novel neuropeptides, which potently modulate arousal and feeding. Single-unit extra...

Ever since a phase II trial of Elan and Wyeth’s experimental vaccine for Alzheimer’s disease (AD) was halted in Jan, 2002, after some patients developed meningoencephalitis (Lancet Neurol 2003; 1: 3), researchers at the two companies have been racing to find out which part of the synthetic protein AN-1792 was responsible for triggering the inflammatory response. On Nov 9 they reported at the So...

Psychosis is a subjective and experiential phenomenon of the mind, influenced by cognitive and socio-cultural patterns of the individual. The neurobiological correlate of this phenomenon is the dysfunction of brain dopaminergic pathways. This article reviews the scientific evidence on the theoretical approaches of the dopaminergic hypothesis of psychosis and its relationship with the reward and...

Dopaminergic deficiency may affect Parkinson's disease patients (PD) in the central as well as the peripheral tissues. In the retina, the neuromodulatory role of the dopaminergic Interplexiform cell layer (IP) plays a major role in the retinal light adaptation and may account for the duration of the negative afterimage. Here we present results showing a significant reduction of negative afterim...

Melanocortinergic and dopaminergic systems are widely distributed in the CNS and have been established as a crucial regulatory component in diverse physiological functions. The pharmacology of both melanocortinergic and dopaminergic systems including their individual receptors, signaling mechanisms, agonists and antagonists has been extensively studied. Several lines of evidence showed that the...

The abuse of psychostimulants, such as methamphetamine (METH), is prevalent in young adults and could lead to long-term adaptations in the midbrain dopamine system in abstinent human METH abusers. Nurr1 is a gene that is critical for the survival and maintenance of dopaminergic neurons and has been implicated in dopaminergic neuron related disorders. In this study, we examined the synergistic e...