Summary
Following injections of horseradish peroxidase in various parts of the monkey cerebellum, the distribution of labelled cells in the nucleus reticularis tegmenti pontis (NRT) has been studied. As a rule, labelled cells are found at all rostrocaudal levels of the NRT regardless of the injection size and site. The densest projection from NRT seems to reach the vermal visual area (lobulus VII), a less dense projection supplies the anterior lobe while the paramedian lobule receives a more sparse projection than the anterior lobe. Very few labelled cells were found in the NRT after injections of crus I and II. The projection is topographically organized so that the dorsomedial part of the NRT supplies lobulus VII, a large central region sends fibres to the anterior lobe (and the cerebellar hemispheres), while the lateral extension of NRT (processus tegmentosus lateralis) is connected with the paramedian lobule.
The results of the present study are compared with those of a preceding one of cortical afferents to NRT. It is concluded that the cortical areas projecting to the NRT seem likely to exert their influences on largely different parts of the cerebellum via the NRT. The present results are also discussed inrelation to termination of other afferent contingents in the NRT, and it is concluded that the NRT is not homogenous anatomically, and consequently different parts of the nucleus would be expected to play somewhat different functional roles.
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References
Allen, G.I., Tsukahara, N.: Cerebrocerebellar communication systems. Physiol. Rev. 54, 957–1006 (1974).
Brodal, A., Brodal, P.: The organization of the nucleus reticularis tegmenti pontis in the cat in the light of experimental anatomical studies of its cerebral cortical afferents. Exp. Brain Res. 13, 90–110 (1971).
Brodal, A., Jansen, J.: The pontocerebellar projection in the rabbit and cat. Experimental investigations. J. Comp. Neurol. 84, 31–118 (1946).
Brodal, P.: Demonstration of a somatotopically organized projection onto the paramedian lobule and the anterior lobe from the lateral reticular nucleus: an experimental study with the horseradish peroxidase method. Brain Res. 95, 221–239 (1975).
Brodal, P.: The corticopontine projection in the rhesus monkey. Origin and principles of organization. Brain 101, 251–283 (1978).
Brodal, P.: The pontocerebellar projection in the rhesus monkey: An experimental study with retrograde axonal transport of horseradish peroxidase. Neuroscience 4, 193–208 (1979a).
Brodal, P.: The cortical projection to the nucleus reticularis tegmenti pontis in the rhesus monkey. Exp. Brain Res. 38, 19–27 (1980).
Colman, D.R., Scalia, F., Cabrales, E.: Light and electron microscopic observations on the anterograde transport of horseradish peroxidase in the optic pathway in the mouse and rat. Brain Res. 102, 156–163 (1976).
Frankfurter, A., Weber, J.T., Harting, J.K.: Brain stem projections to lobule VII of the posterior vermis in the squirrel monkey: as demonstrated by the retrograde axonal transport of tritiated horseradish peroxidase. Brain Res. 124, 135–139 (1977).
Harting, J.K.: Descending pathways from the superior colliculus: An autoradiographic analysis in the rhesus monkey (Macaca mulatta). J. Comp. Neurol. 173, 583–612 (1977).
Hoddevik, G.H.: The projection from the nucleus reticularis tegmenti pontis onto the cerebellum in the cat. Anat. Embryol. 153, 227–242 (1978).
Jansen, J., Brodal, A.: Experimental studies on the intrinsic fibers of the cerebellum. The corticonuclear projection in the rabbit and in the monkey (Macacus rhesus). Norske Vid. Akad., Oslo, Avh. I. Mat. Naturv. 3, 1–50 (1942).
Lafleur, J., Lean, J. De, Poirier, L.J.: Physiopathology of the cerebellum in the monkey. Part 1. Origin of cerebellar afferent nervous fibers from the spinal cord and brain stem. J. Neurol. Sci. 22, 471–490 (1974).
Larsell, O.: The cerebellum of the cat and the monkey. J. Comp. Neurol. 99, 135–199 (1953).
McCrea, R.A., Bishop, G.A., Kitai, S.T.: Electrophysiological and horseradish peroxidase studies of precerebellar afferents to the nucleus interpositus anterior. II. Mossy fiber system. Brain Res. 122, 215–228 (1977).
Olszewski, J., Baxter, D.: Cytoarchitecture of the human brain stem. New York, Basel: Karger 1954.
Somana, R., Walberg, F.: Cerebellar afferents from the paramedian reticular nucleus studied with retrograde transport of horseradish peroxidase. Anat. Embryol. 154, 353–368 (1978).
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Brodal, P. The projection from the nucleus reticularis tegmenti pontis to the cerebellum in the rhesus monkey. Exp Brain Res 38, 29–36 (1980). https://doi.org/10.1007/BF00237927
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DOI: https://doi.org/10.1007/BF00237927