Anatomical and histochemical studies of the globus pallidus and related basal ganglia nuclei
William Alan Staines
1983
The anatomical organization of the connections of the major components of the basal ganglia was investigated in detail. A sensitive procedure for the simultaneous study of afferents and efferents was carried out on the striatum (CP), globus pallidus (GP), and substantia nigra (SN). Previously well characterized connections of the CP were confirmed, additional evidence for a projection to the CP from the ventromedial nucleus of the thalamus was obtained and a topographically organized projection
more »
... to the CP from the GP was discovered. A similar study of the SN revealed a nigral projection to the ipsilateral lateral dorsal nucleus of the thalamus and nigral input from the contralateral posterior lateral hypothalamus. The projection of the GP to the SN was found to be linked topographically to the striatonigral and pallidostriatal pathways. A study of the connections of the GP confirmed a massive projection from the CP and provided further evidence of a reciprocal connection. In addition, pallidal innervations of the entopeduncular nucleus and reticular nucleus of the thalamus were indicated. Because of the potential importance of a pallidostriatal projection and the significant number of technical difficulties associated with its demonstration, additional experiments were carried out to confirm the presence of this pathway and to determine its anatomical relationship to other basal ganglia connections. Retrograde labelling of pallidostriatal neurons, studied with electron microscopy and in combination with lesions of the striatum, confirmed that pallidal neurons project either to or through the striatum. Evidence for possibly two groups of pallidal neurons that project to the CP was obtained, and it was observed that both of these cell groups were congruent with the striatopallidal terminal fields. Comparisons of the distribution of cells retrogradely labelled after tracer injections into the cortex and CP in combination with histochemistry for acetylcholinesterase demonstrated that the population of pallidal neu [...]
doi:10.14288/1.0076985
fatcat:fr3vftaw5rf7lptudh6kcwliby