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The nigrostriatal pathway is a neural pathway that connects the substantia nigra with the striatum. It is one of the four major dopamine pathways in the brain, and is particularly involved in the production of movement, as part of a system called the basal ganglia motor loop.
Loss of dopamine neurons in the substantia nigra is one of the main pathological features of Parkinson's disease, leading to a marked reduction in dopamine function in this pathway. The symptoms of the disease typically do not show themselves until 80-90% of dopamine function has been lost.
This pathway is also implicated in producing tardive dyskinesia, one of the side-effects of antipsychotic drugs. These medications (particularly the older typical antipsychotics) block D2 dopamine receptors in multiple pathways in the brain.
The desired clinical effect of reducing psychotic symptoms is thought to be associated with blocking dopamine function in the mesolimbic pathway only. However, as many of these drugs are not selective, they block dopamine in all pathways. When this happens in the nigrostriatal pathway, similar movement problems to those found in Parkinson's disease can occur.
Other major dopamine pathways include:
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Brain: telencephalon (cerebrum, cerebral cortex, cerebral hemispheres) |
| primary sulci/fissures |
medial longitudinal, lateral, central, parietoöccipital, calcarine, cingulate |
| frontal lobe |
precentral gyrus (primary motor cortex, 4), precentral sulcus, superior frontal gyrus (6, 8), middle frontal gyrus (46), inferior frontal gyrus (Broca's area, 44-pars opercularis, 45-pars triangularis), prefrontal cortex (orbitofrontal cortex, 9, 10, 11, 12, 47) |
| parietal lobe |
postcentral sulcus, postcentral gyrus (1, 2, 3, 43), superior parietal lobule (5), inferior parietal lobule (39-angular gyrus, 40), precuneus (7), intraparietal sulcus |
| occipital lobe |
primary visual cortex (17), cuneus, lingual gyrus, 18, 19 (18 and 19 span whole lobe) |
| temporal lobe |
transverse temporal gyrus (41-42-primary auditory cortex), superior temporal gyrus (38, 22-Wernicke's area), middle temporal gyrus (21), inferior temporal gyrus (20), fusiform gyrus (36, 37) |
| limbic lobe/fornicate gyrus |
cingulate cortex/cingulate gyrus, anterior cingulate (24, 32, 33), posterior cingulate (23, 31),
isthmus (26, 29, 30), parahippocampal gyrus (piriform cortex, 25, 27, 35), entorhinal cortex (28, 34) |
| subcortical/insular cortex |
rhinencephalon, olfactory bulb, olfactory tract, corpus callosum (splenium, genu, rostrum), lateral ventricles, septum pellucidum, ependyma, internal capsule, corona radiata, external capsule, fornix (commissure of fornix), anterior commissure, posterior commissure |
| hippocampal formation |
dentate gyrus, hippocampus, subiculum |
| basal ganglia |
striatum (caudate nucleus, putamen), lentiform nucleus (putamen, globus pallidus), claustrum, extreme capsule, amygdala, nucleus accumbens |
| Some categorizations are approximations, and some Brodmann areas span gyri. |
