Dopamine regulation

Sakamoto K, Liu C., Kasamatsu M. et al. (2005). Dopamine regulates melanopsin mRNA expression in intrinsically photoresponsive retinal ganglion cells. Eur. J. Neurosci. 22, 3129-36. 

The possibility that dopamine regulates neostriatal GABA-ergic function receives no support from in vitro superfusion experiments determining the release of [3HJ-GABA from slices of rat neostriatum (5 3). The D-2 receptor agonist RU 24926 is... 

Mela nocy te-stimula ting hormone (a-MSH) Ac- Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly-Lys-Pro-Val- NH2C Unknown MSH release-inhibiting factor (MIF) most likely dopamine Regulates pigment production by melanocytes... 

Hemmings HC, Jr, Greengard P, Tung HY, Cohen P (1984b) DARPP-32, a dopamine-regulated neuronal phosphoprotein, is a potent inhibitor of protein phosphatase-1. Nature 370 503-505. 

Reynolds JNJ, Wickens JR (2000) Substantia nigra dopamine regulates synaptic plasticity and membrane potential fluctuations in the rat neostriatum, in vivo. Neuroscience 99 199-203. 

Wickens JR (2000) Dopamine regulation of synaptic plasticity in the neostriatum a cellular model of reinforcement. In Miller R, Wickens JR (Eds), Brain dynamics and the striatal complex, pp. 65-76. Harwood Academic. 

From these various analyses, it is clear that dopamine regulation of the striatum does not simply control detailed movement, but is involved in the selection and initiation of appropriate goal directed actions (Dunnett and Robbins, 1992 Robbins and Everitt, 1992), as influenced by motor learning (i.e. the acquisition of skills and habits Mishkin et al., 1984 Jog et al., 1999), in the context of motivational information related to needs and rewards (Suri and Schultz, 1999). Theoretical formulations of this process have moved away from the neuropsychological theory, although still conceptually useful, to mathematical and neural network modeling (Houk et al., 1995 Servan-Schreiber et al., 1998), which is beyond the scope of the present review. 

Because VMAT regulates the level of cytosolic monoamines, researchers have examined a role for VMAT in disease states. Although no direct pathological links to aberrant VMAT function have been described, altered dopamine regulation can lead to drug addiction, Parkinson s disease, and schizophrenia (Mazei-Robison et al.,... 

Oestreicher E, Arnold W, Ehrenberger K, Felix D (1997) Dopamine regulates the glutamatergic inner hair cell activity in guinea pigs. Hear Res 707 46-52. 

Kusunoki, K., Taniyama, K., and Tanaka, C. (1985). Dopamine regulation of [ H]acetylcholine release from guinea pig stomach. J. Pharmacol. Exp. Ther. 234, 713-719. 

The importance of dopamine in neural transmission is emphasized by the number of major neurological diseases that are associated with improper dopamine regulation. The earliest indication of this type of defect was the finding that dopamine levels are abnormally low in a particular region of the brain of patients with Parkinsonism, a severe neurological disorder. Attempts to treat such patients with dopamine were futile, because after injection, dopamine does not cross the bloodbrain barrier. However, the dopamine precursor, dopa, does cross the bloodbrain barrier. For many individuals with Parkinsonism, daily doses of dopa have provided dramatic clinical improvement. 

Cao et uL, 2005), whereas dopamine regulates ACh release in the striatum (Acquas and Di Chiara, 2001 Alcantara ei ai, 2003). Nicotinic [St subunit-receptor knockout mice show markedly less depolarization-induced dopamine release (Picciotto er al 1998). Glutamatergic inputs from the thalamus can also intluence cholinergic intemeurons, increasing striatal ACh release Baldi ei ai, 1995 Console et ai, 1990 Pollack, 2001). 

E. coli. Phospholipase C, also a metalloenzyme, can also be inhibited by aminoglycosides. Inhibition of dopamine regulating P-type Ca channels by neomycin can also be considered a toxic pathway. Lastly, aminoglycosides have been shown to bind triple-helical DNA, which are known to exist in biological systems as potential regulators of gene expression. ... 

As mentioned in the chapter opening, Parkinson s disease is a neurodegenerative disorder marked by a decreased production of dopamine in the brain. Since dopamine regulates motor function, the decrease in dopamine leads to impaired motor control. Although there is no cure for Parkinson s disease, the symptoms can be treated by a variety of methods. The most effective course of treatment is to administer a drug called L-dopa, which is converted into dopamine in the brain ... 

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