Introduction: Parkinson disease (PD) is the second frequent human neurodegenerative disease following Alzheimer. This illness is caused by degeneration of dopaminergic neurons in the compact part of substantia nigra (SNpc). Clinical demonstrations are observable when 70% of dopaminergic neurons in SNpc and 80% of dopaminergic terminals in striatum have been degenerated. Characterization of non-...

Neurons that produce dopamine as a neurotransmitter constitute a heterogeneous group involved in the control of various behaviors and physiology. In mammals, dopaminergic neurons are found in distinct clusters mainly located in the ventral midbrain and the caudal forebrain [1]. Although much is known about midbrain dopaminergic neurons, development of diencephalic dopaminergic neurons is poorly...

Objective(s): Parkinson’s disease (PD) is characterized by motor and cognitive dysfunctions. The progressive degeneration of dopamine-producing neurons that are present in the substantia nigra pars compacta (SNpc) has been the main focus of study and PD therapies since ages.Materials and Methods: In this manuscript, a systematic revision...

The proper functioning of the dopaminergic system requires the coordinated formation of projections extending from dopaminergic neurons in the substantia nigra (SN), ventral tegmental area (VTA) and retrorubral field to a wide array of forebrain targets including the striatum, nucleus accumbens and prefrontal cortex. The mechanisms controlling the assembly of these distinct dopaminergic cell cl...

Development of midbrain dopaminergic neurons is known to depend on inductive signals derived from the ventral midline, including Sonic hedgehog (Shh) as one of the identified molecules. Here we show that in addition to Shh, transforming growth factor (TGF)-beta is required for both induction and survival of ventrally located midbrain dopaminergic neurons. Like Shh, TGF-beta is expressed in earl...

Dopaminergic neurons develop at distinct anatomical sites to form some of the major neuromodulatory systems in the vertebrate brain. Despite their relevance in neurodegenerative diseases and the interests in reconstitutive therapies from stem cells, mechanisms of the neurogenic switch from precursor populations to dopaminergic neurons are not well understood. Here, we investigated neurogenesis ...

ABSTRACT Background and Objective: Parkinson's disease (PD) is an age-related neurodegenerative disorder with massive loss of dopaminergic neurons in the substantia nigra pars compacta. L-Dihydroxyphenylalanine (L-DOPA) substitution is still the gold standard therapy for PD. However, there has been little information available on neuroprotective and regenerative therapies for PD. Due to the neu...

Phasic activation of dopaminergic neurons is associated with reward-predicting cues and supports learning during behavioral adaptation. While noncontingent activation of dopaminergic neurons in the ventral tegmental are (VTA) is sufficient for passive behavioral conditioning, it remains unknown whether the phasic dopaminergic signal is truly reinforcing. In this study, we first targeted the exp...

At least 70% of the afferents to substantia nigra dopaminergic neurons are GABAergic. The vast majority of these arise from the neostriatum, the external globus pallidus and the substantia nigra pars reticulata. Nigral dopaminergic neurons express both GABA(A) and GABA(B) receptors, and are inhibited by local application of GABA(A) or GABA(B) agonists in vivo and in vitro. However, in vivo, syn...

introduction: nigrothalamocortical tract is one of the main outputs of the basal nuclei, but its role in motor disturbances is vauge, because there is little informations on its connection structure. some electrophysiological and pharmacological surveys report that none-dopaminergic outputs originate from reticular part of substantia nigra and end at thalamus. in this study the topographical co...