Corpus striatum

Besides those in the corpus striatum, there are large accumulations of dopamine terminals in some nuclei of the limbic system such as the nucleus accumbens and the olfactory tubercle. The l-DOPA-induced increase in rat motor activity might be evoked, at least partly, by a stimulation of postsyn-aptic dopamine receptors in the nucleus accumbens since local application of dopamine bilaterally to this region markedly enhanced the rat motor activity (PijNENBURG and Van Rossum 1973). 

Nitric oxide ( NO) may be very much involved in the expression of associative increase in extracellular dopamine in the nucleus accumbens (Afa-nas ev et al. 2000). 

Small nerve cells (10-15 pm in diameter) are very numerous (Mori 1966). Groups of round dense bodies, 0.1-0.7 pm in diameter, are usually found in the Golgi region. They are filled with numerous fine granules of 8 nm diameter, spacing a 

Giant neurones are elongated reaching 20 pm in width and 30-60 pm in length (Dimova et al. 1980). Perinuclear cytoplasm is rich in both lysoso-mes and Golgi zones of considerable size and with narrow lamellae. 

Neutron activation analysis of iron in the human nucleus caudatus and putamen from patients aged 23 to 66 y resulted in 8.30 0.46 and 8.78 0.55 x 10 terms of element weight per unit dried tissue, respectively (HOck etal. 1975). 

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The nigrostriatal tract is one of the four main dopaminergic pathways in the central nervous system. About 75% of the dopamine in the brain occurs in the nigrostriatal pathway with its cell bodies in the substantia nigra, whose axons project in the corpus striatum. Degeneration of the dopaminergic neurons in the nigrostriatal system results in Parkinsons disease. 

Russell, WL, Henry, DP, Phebus, LA and Clemens, JA (1990) Release of histamine in rat hypothalamus and corpus striatum in vivo. Brain Res. 512 95-101. 

The motor activation produced by psychomotor stimulants has been long associated with the midbrain dopamine systems. While focused stereotyped behavior produced by high doses of indirect sympathomimetics is blocked by removal of dopamine terminals in the corpus striatum (Creese and Iversen 1975), the locomotor activation produced by low doses of indirect sympathomimetics is blocked by removal of dopamine terminals in the region of the nucleus accumbens (Kelly et al. 1975). This dopaminergic substrate for psychostimulant effects appears selective for the indirect sympathomimetics in that dopamine lesions to the region of the nucleus... 

Kelly, P.H. Seviour, P. and Iversen, S.D. Amphetamine and apomorphine response in the rat following 6-OHDA lesions of the nucleus accumbens septi and corpus striatum. Brain Res 94 507-522, 1975. 

FIGURE 29-1. Anatomy of the extrapyramidal system. The extrapyramidal motor system controls muscle movement through a system of pathways and nerve tracts that connect the cerebral cortex, basal ganglia, thalamus, cerebellum, reticular formation, and spinal neurons. Patients with Parkinson s disease have a loss of dopamine neurons in the substantia nigra in the brain stem that leads to depletion of dopamine in the corpus striatum. The corpus striatum is made up of the caudate nucleus and the lentiform nuclei that are made up of the putamen and the globus pallidus. 

This benzylisoquinoline alkaloid inhibits in vitro the specific bonding of [3H] dopamine to dopamine receptors and abrogates amphetamine-induced circling behavior in rodents with unilateral degeneration of dopaminergic neurons in the corpus striatum (109). 

Liang, N.Y. and Rutledge, C.O., Comparison of the release of [3H]dopamine from isolated corpus striatum by amphetamine, fenfluramine and unlabeled dopamine, Biochem. Pharmacol., 31, 983, 1982. 

Samuel, D., Lynch, M.A., and Littleton, J.M., Picrotoxin inhibits the effect of ethanol on the spontaneous efflux of [3H]-dopamine from superfused slices of rat corpus striatum, Neuropharmacology, 22, 1412, 1983. 

Unlike many chemicals in the brain, neurotransmitters are not homogeneously distributed, but concentrated in certain regions. For example, almost two-thirds of the dopamine in the brain is found in the bilateral nigrostriatal (mesostriatal) tract (pathway), where the neuronal cell bodies are located in the substantia nigra and the axons terminate in the corpus striatum. When over 85% of these dopaminergic neurons are lost, the characteristic motor dysfunction of Parkinson s disease is seen. 

Corpus striatum A forebrain basal ganglion comprising the caudate nucleus and... 

Putamen A forebrain basal ganglion and part of the corpus striatum. 

The exact mechanism by which the allele exerts its effects on predisposition to tobacco addiction is not known. People with one or more of the variant alleles are believed to have reduced numbers of dopamine receptors in the corpus striatum... 

The extent of receptor supersensitivity after unilateral nigrostriatal lesions can be quantified by measuring the extent of rotational behavior. After selective nigrostriatal lesions have been produced in rats by injections of 6-hydroxydopamine into the substantia nigra, the number of dopamine receptors in the ipsilateral corpus striatum increases markedly, and the increase in the number of receptors may correlate with the extent of behavioral supersensitivity as monitored by rotational behavior [52]. Thus, the increase in receptor density appears to play a role in the behavioral supersensitivity of these animals. 

Glatt, C. and Synder, S. H. Cloning and expression of an adenylyl cyclase localized to the corpus striatum. Nature 361 536-538,1993. 

Poddar MK, Dewey WL. 1983. Kepone induced changes in the synaptosomal uptake and release of dopamine in corpus striatum and norepinephrine in hypothalamus. IRCS Medical Science Library Compendium 11 (7) 632-633. 

Mice exposed for 28 days to phenol in drinking water exhibited a significant reduction in dopamine level in the corpus striatum at the 1.8 mg/kg/day dose, and significantly decreased levels of norepinephrine, serotonin, and 5-hydroxyindoleacetic acid in the hypothalamus at the 6.2 mg/kg/day dose (Hsieh et al. 1992). Levels of neurotransmitters in other brain regions were also significantly altered at higher doses of phenol. 

Dluzen DE, Anderson LI (1997) Estrogen differentially modulates nicotine-evoked dopamine release from the striatum of male and female rats. Neurosci Lett 230(2) 140-142 Dluzen DE, Ramirez VD (1990) In vitro progesterone modulation of amphetamine-stimulated dopamine release from the corpus striatum of ovariectomized estrogen-treated female rats response characteristics. Brain Res 517(1-2) 117-122 Donny EC, Caggiula AR, et al (2000) Nicotine self-administration in rats estrous cycle effects, sex differences and nicotinic receptor binding. Psychopharmacology 151(4) 392-405... 

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