Striatal efferents

In addition to presynaptic receptors, autoradiographic studies have indicated the presence of postsynaptic H3-receptor binding sites as well. Chemical destruction of postsynaptic structures in the striatum using quinolinic and kainic acid resulted in a marked decrease of striatal H3-receptor binding sites (Cumming et al., 1991 Pollard et al., 1993 Ryu et al., 1994). Consequently, a major part of the striatal H3-receptors may be located on striatal GABA neurons, representing more than 85% of the striatal efferents (Kita Kitai, 1988). 

Surmeier DJ, Kitai ST (1994) Dopaminergic regulation of striatal efferent pathways. Cur Opin Neurobiol 4 915-919. 

Bernard V, Dumartin B, Lamy E, Bloch B (1993) Fos immunoreactivity after stimulation or inhibition of muscarinic receptors indicates anatomical specificity for cholinergic control of striatal efferent neurons and cortical neurons in the rat. Eur. J. Neurosci, 5, 1218-1225. 

Fox CA, Rafols JA (1976) The striatal efferents in the globus pallidus and substantia nigra. In Yahr MD (Ed.) The Basal Ganglia, pp 37-55. Raven Press, New York. 

Jimenez CJ, Graybiel AM (1989) Compartmental origins of striatal efferent projections in the cat. Neuroscience, 32, 297-321. 

As a major fraction of striatal efferent fibers appear to be GABAergic in nature (Fonnum et at., 1978) and only other neurotransmitters will be... 

In animal models of HD, transplanted striatal cells have survived, grow n and established afferent and efferent connections (Freeman et al., 2000). One open label human trial indicated that grafts may have restored function (Hauser et al., 2002). Recipients show ed cognitive and motor improvements thatw ere associated wdth reductions in striatal and cortical hypometaboiism. The success of grafting may be sensitive to the age of the donor and to the degree of neuronal loss in the patient. Clinical trials are in early phases and there still needs to be resolution of a number of technical issues (Gardian and Vecsei, 2004). 

Sadikot AF, Parent A, Smith Y, Bolam JP (1992) Efferent connections of the centromedian and parafascicular thalamic nuclei in the squirrel monkey a light and electron microscopic study of the thalamostriatal projection in relation to striatal heterogeneity. J Comp Neurol. 20 228-242. 

Van der Kooy D, Carter D (1981) The organization of the efferent projections and striatal afferents of the entopeduncular nucleus and adjacent areas in the rat. Brain Res., 211, 15-36. 

In hypokinetic disorders, the discharge of efferent striatal neurons is diminished in the direct and increased in the indirect way, so that an inhibition of thalamocortical connections originates from a... 

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