Midbrain dopaminergic

Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-indueed parkinsonian syndrome in Macaca fascicularis Which midbrain dopaminergic neurons are lost Neuroscience 24 161-174, 1988. 

Figure 7.4 Summary of some of the wide array of afferent and efferent connections of midbrain dopaminergic neurons (SN/A9, RRF/A8, and VTA/A10 in center of figure). This emphasizes their potential involvement in coordination of seemingly disparate behaviors inclusive of the sleep-wake state of the organism. Abbreviations BP, blood pressure BST, bed nucleus of the stria terminalis CEA, central nucleus of the amygdala MEA, midbrain extrapyramidal area NTS, nucleus of the solitary tract O2, oxygen tension PPN, pedunculopontine tegmental nucleus RRF, retrorubral field SN, substantia nigra VTA, ventral tegmental area.

Klink, R., de Kerchove d Exaerde, A., Zoli, M., Changeux, J.P. Molecular and physiological diversity of nicotinic acetylcholine receptors in the midbrain dopaminergic nuclei. J. Neurosci. 21 1452, 2001. 

Persephin (PSPN) has been shown to promote the survival of basal forebrain neurons including both cholinergic neurons. Moreover, it supports midbrain dopaminergic neurons. PSPN is expressed in the striatum, consistent with its role as a target-derived trophic factor for these cells. 

McCallum SE, Parameswaran N, Bordia T, Fan H, McIntosh JM, Quik M (2006) Differential regulation of mesolimbic alpha 3/alpha 6 beta 2 and alpha 4 beta 2 nicotinic acetylchohne receptor sites, function after long-term oral nicotine to monkeys. J Pharmacol Exp Ther318 381-388 McKay BE, Placzek AN, Dani JA (2007) Regulation of synaptic transmission and plasticity by neuronal nicotinic acetylchohne receptors. Biochem Pharmacol 74 1120-1133 Mena-Segovia J, Winn P, Bolam JP (2008) Chohnergic modulation of midbrain dopaminergic systems. Brain Res Rev 58 265-271... 

Gonon, Francois G. 1988. "Nonlinear Relationship Between Impulse Flow and Dopamine Released by Midbrain Dopaminergic Neurons as Studied by In Vivo Electrochemistry." Neuroscience 24 19-28. 

Nirenberg MJ, Chan J, Liu Y, Edwards RH, Pickel VM (1996) Ultrastructural localization of the vesicular monoamine transporter-2 in midbrain dopaminergic neurons potential sites for somatodendritic storage and release of dopamine. J Neurosci 16 4135 1145. 

Sulzer D, Rayport S (1990) Amphetamine and other psychostimulants reduce pH gradients in midbrain dopaminergic neurons and chromaffin granules a mechanism of action. Neuron 5 797-808. 

The consequence of the combination of D2 and 5-HT2 receptor antagonism is therefore the selective enhancement of dopaminergic activity in the prefrontal cortex and, as a consequence, a correction of the regional imbalance between the cortical and midbrain dopaminergic systems. 

Besides its involvement in behavioural symptoms, there might exist in analogy to AD a direct effect of NE on the dopaminergic system and thereby involvement in the motor symptoms. There is some evidence, that NE neurons of the LC directly innervate midbrain dopaminergic neurons as stimulation of the LC facilitates firing of neurons of the substantia nigra (Grenhofif et al., 1993). 

Garcia-Gil, F., Ramos, J. A., Rubino, T., Parolaro, D., and Fernandez-Ruiz, J. J. (1998). Perinatal delta9-tetrahydrocannabinol exposure did not alter dopamine transporter and tyrosine hydroxylase mRNA levels in midbrain dopaminergic neurons of adult male and female rats. Neurotoxicol. Teratol. 20, 549—553. 

DiMascio, M., DiGiovanni, G., DiMatteo, V., and Esposito, E., Decreased chaos of midbrain dopaminergic neurons after serotonin denervation, Neuroscience, Vol. 92, No. 1, 1999, pp. 237-243. 

Chiodo, L. A., Bunney, B. S. (1983). Typical and atypical neuroleptics Differential effects of chronic administration on the activity of A9 and A10 midbrain dopaminergic neurons. Journal of Neuroscience, 3, 1607-1619. 

Gronier B, Rasmussen K. 1999. Pertussis toxin treatment differentially affects cholinergic and dopaminergic receptor stimulation of midbrain dopaminergic neurons. Neuropharmacology 38 1903-1912. 

Kumamoto N, Matsuzaki S, Inoue K, Hattori T, Shimizu S, et al. 2006. Hyperactivation of midbrain dopaminergic system in schizophrenia could be attributed to the down-regulation of dysbindin. Biochem Biophys Res Commun 345 904-909. 

The distinction of the midbrain dopaminergic system into a dorsal and a ventral tier is based on the main cellular features mentioned above, as well as on distinct neurochemical features and pattern of connectivity, which will be presented in the following sections but are summarized here. 

Fig. 12. The diagram, redrawn from Fallon and Loughlin (1995), summarizes the distribution in the rat of midbrain dopaminergic neurons which give origin to different sets of telencephalic projections. Abbreviations CP, cerebral peduncle ml, medial lemniscus MT, medial terminal nucleus of the accessory optic tract SNc, substantia nigra, pars compacta SN1, substantia nigra, pars lateralis SNr, substantia nigra, pars reticulata VTA, ventral tegmental area.

For many years dendritic release of the neurotransmitter was considered a peculiarity of the midbrain dopaminergic neurons. However, this mechanism of release has now been ascertained for other neuroactive substances as well, including other neurotransmitters. 

Connexin 36 expression in midbrain dopaminergic cells and gap junctions... 

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