Summary
The organization of the afferent projections to the lateral reticular nucleus of the rat was investigated following placement of horseradish peroxidase-conjugated wheatgerm agglutinin into the red nucleus, fastigial nucleus, various levels of the spinal cord or the sensorimotor area of the cerebral cortex. The pattern of distribution of anterogradely labelled profiles visualized with tetramethylbenzidine revealed that the caudal three-fourths of the lateral reticular nucleus received a large, topographically organized projection from the entire length of the contralateral spinal cord. The lateral part of the rostral half of the lateral reticular nucleus received a small projection from the contralateral red nucleus, the dorsal part of the middle third of the nucleus received a diffuse projection from the contralateral fastigial nucleus, and the extreme rostromedial part of the nucleus received a sparse projection from the contralateral cerebral cortex. The dorsal part of the middle third of the lateral reticular nucleus also received a small projection from the ipsilateral cervical spinal cord. The distribution of afferent fibres from different levels of the spinal cord, red nucleus, and fastigial nucleus overlapped substantially in the middle third of the lateral reticular nucleus, whereas the cerebral cortical receiving area was separate. These data suggest that the middle third of the lateral reticular nucleus integrates spinal and supraspinal impulses to the cerebellum, while the rostral part of the nucleus is involved in a separate cerebral cortico-cerebellar pathway.
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Abbreviations
- DSC :
-
dorsal spinocerebellar
- ECN :
-
external cuneatus nucleus
- F :
-
fastigial nucleus
- FRA :
-
flexor reflex afferents
- HRP :
-
horseradish peroxidase
- IO :
-
inferior olivary nucleus
- IP :
-
interpositus nucleus
- LRN :
-
lateral reticular nucleus
- MCP :
-
magnocellular portion
- M-LRN :
-
magnocellular LRN
- NA :
-
nucleus ambiguus
- NSTT :
-
nucleus of the spinal tract of the trigeminal nerve
- PCP :
-
parvicellular portion
- R :
-
red nucleus
- STP :
-
subtrigeminal portion
- STT :
-
spinal tract of the trigeminal nerve
- TMB :
-
tetramethylbenzidine
- VSC :
-
ventral spinocerebellar
- WGA :
-
wheatgerm agglutinin
- b-VFRT :
-
bilateral ventral flexor reflex tract
- c-VFRT :
-
contralateral ventral flexor reflex tract
- i-FT :
-
ipsilateral forelimb tract
References
Batton RR, Jayaraman D, Ruggiero D, Carpenter MB (1977) Fastigial afferent projections in the monkey: an autoradiographic study. J Comp Neurol 174:281–306
Brodal A (1949) Spinal afferents to the lateral reticular nucleus of the medulla oblongata in the cat. An experimental study. J Comp Neurol 91:259–295
Brodal P (1975) 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
Brodal P, Marsala J, Brodal A (1967) The cerebral cortical projection to the lateral reticular nucleus in the cat, with special reference to the sensorimotor cortical areas. Brain Res 6:252–274
Brodal P, Dietrichs E, Bjaalie JG, Nordby T, Walberg F (1983) Is lectin-coupled horseradish peroxidase taken up and transported by undamaged as well as damaged fibres in the central nervous system? Brain Res 278:1–9
Bruckmoser P, Hepp-Raymond M-C, Wiesendanger M (1970) Cortical influence on single neurons of the lateral reticular nucleus of the cat. Exp Neurol 26:239–252
Clendenin M, Ekerot C-F, Oscarsson O, Rosen I (1974a) Functional organization of two spinocerebellar paths relayed through the lateral reticular nucleus in the cat. Brain Res 69:140–143
Clendenin M, Ekerot C-F, Oscarsson O, Rosen I (1974b) The lateral reticular nucleus in the cat. II. Organization of component activated from bilateral ventral reflex tract (bVFRT). Exp Brain Res 21:487–500
Clendenin M, Ekerot C-F, Oscarsson O (1974c) The lateral reticular nucleus in the cat. III. Organization of component activated from ipsilateral forelimb tract. Exp Brain Res 21:501–513
Corvaja N, Grofova I, Pompeiano O, Walberg F (1977a) The lateral reticular nucleus in the cat. I. An experimental anatomical study of its spinal and supraspinal afferent connections. Neuroscience 2:537–553
Corvaja N, Grofova I, Pompeiano O, Walberg F (1977b) The lateral reticular nucleus in the cat. II. Effects of lateral reticular lesions on posture and reflex movements. Neuroscience 2:929–943
Courville J (1966) Rubrobulbar fibres to the facial nucleus and the lateral reticular nucleus (nucleus of the lateral funiculus). An experimental study in the cat with silver impregnation methods. Brain Res 1:317–337
Dietrichs E, Walberg F (1979) The cerebellar projection from the lateral reticular nucleus as studied with retrograde transport of horseradish peroxidase. Anat Embryol 155:273–290
Edwards SB (1972) The ascending and descending projections of the red nucleus in the cat: an experimental study using an autoradiographic tracing method. Brain Res 48:45–63
Ekerot C-F, Oscarsson O (1975) Inhibitory spinal paths to the lateral reticular nucleus. Brain Res 99:157–161
Flumerfelt BA, Hrycyshyn AW, Kapogianis EM (1982a) Spinal projections to the lateral reticular nucleus in the rat. Anat Embryol 165:345–359
Flumerfelt BA, Kapogianis EM, Hrycyshyn AW (1982b) An ultrastructural study of the lateral reticular nucleus in the rat. Anat Embryol 164:243–253
Gerfen CR, O'Leary DDM, Cowan WM (1982) A note on the transneuronal transport of wheat germ agglutinin-conjugated horseradish peroxidase in avian and rodent visual systems. Exp Brain Res 48:443–448
Hinman A, Carpenter MB (1959) Efferent fiber projections of the red nucleus in the cat. J Comp Neurol 113:61–81
Hrycyshyn AW, Flumerfelt BA (1981a) Cytology and synaptology of the lateral reticular nucleus of the cat. J Comp Neurol 197:459–475
Hrycyshyn AW, Flumerfelt BA (1981b) A light microscopic investigation of the afferent connections of the lateral reticular nucleus in the cat. J Comp Neurol 197:503–516
Hrycyshyn AW, Flumerfelt BA (1981c) An electron microscopic study of the afferent connections of the lateral reticular nucleus of the cat. J Comp Neurol 197:503–516
Hrycyshyn AW, Flumerfelt BA, Anderson WA (1982) A horseradish peroxidase study of the projections from the lateral reticular nucleus to the cerebellum in the rat. Anat Embryol 165:1–18
Jones EG, Leavitt RY (1974) Retrograde axonal transport and the demonstration of non-specific projections to the cerebral cortex and striatum from thalamic intralaminar nuclei in the rat, cat, and monkey. J Comp Neurol 154:349–378
Kapogianis EM, Flumerfelt BA, Hrycyshyn AW (1982) Cytoarchitecture and cytology of the lateral reticular nucleus in the rat. Anat Embryol 164:229–242
Kitai ST, De France JF, Hatada K, Kennedy DT (1974) Electrophysiological properties of lateral reticular nucleus cells: II. Synaptic activation. Exp Brain Res 21:419–432
Künzle H (1973) The topographic organization of spinal afferents to the lateral reticular nucleus of the cat. J Comp Neurol 149:103–116
Künzle H, Wiesendanger M (1974) Pyramidal connections to the lateral reticular nucleus in the cat: a degeneration study. Acta Anat (Basel) 88:105–114
Kuypers HGJ (1958a) An anatomical analysis of corticobulbar connexions to the pons and lower brain stem in the cat. J Anat 92:198–218
Kuypers HGJ (1958b) Some projections from the pericentral cortex to the pons and the lower brain stem in monkey and chimpanzee. J Comp Neurol 111:221–251
Kuypers HGJ (1958c) Corticobulbar connexions to the pons and lower brain stem in man. An anatomical study. Brain 81:364–388
Lundberg A, Oscarsson O (1962) Two ascending spinal pathways in the ventral part of the cord. Acta Physiol Scand 54:270–286
Martin GF, Andrezik J, Crutcher K, Linauts M, Panneton M (1977) The lateral reticular nucleus of the opossum (Didelphis virginiana). II. Connections. J Comp Neurol 174:151–186
Menetrey D, Roudier F, Besson JM (1983) Spinal neurons reaching the lateral reticular nucleus as studied in the rat by retrograde transport of horseradish peroxidase. J Comp Neurol 220:439–452
Mesulam M-M (1978) Tetramethyl benzidine for horseradish peroxidase neurohistochemistry: a non-carcinogenic blue reactionproduct with superior sensitivity for visualizing neural afferents and efferents. J Histochem Cytochem 26:106–117
Mesulam M-M (1982) Principles of horseradish peroxidase neurohistochemistry and their applications for tracing neural pathways. In: Mesulam MM (ed) Tracing neural connections with horseradish peroxidase. Wiley, New York, pp 1–151
Mizuno N, Nakamura Y (1973) An electron microscope study of the spinal afferents to the lateral reticular nucleus of the medulla oblongata in the cat. Brain Res 53:187–191
Mizuno N, Konishi A, Nakamura Y (1975) An electron microscope study of synaptic organization in the lateral reticular nucleus of the medulla oblongata in the cat. Brain Res 94:369–381
Mizuno N, Mochizuki K, Akimoto C, Matsushima R, Nakamura Y (1973) Rubrobulbar projections in the rabbit. A light and electron microscopic study. J Comp Neurol 147:267–280
Morin F, Kennedy DT, Gardner E (1966) Spinal afferents to the lateral reticular nucleus. I An histological study. J Comp Neurol 126:511–522
Naus CG, Flumerfelt BA, Hrycyshyn AW (1984) Topographic specificity of aberrant cerebellorubral projections following neonatal hemicerebellectomy in the rat. Brain Res 309:1–15
Paxinos G, Watson C (1982) The rat brain in stereotaxic coordinates. Academic Press, Sydney
Qvist H (1989) The cerebellar nuclear afferent and efferent connections with the lateral reticular nucleus in the cat as studied with retrograde transport of WGA-HRP. 179:471–483
Qvist H, Dietrichs E, Walberg F (1984) An ipsilateral projection from the red nucleus to the lateral reticular nucleus in the cat. Anat Embryol 170:327–330
Rosen I, Scheid P (1973) Responses to nerve stimulation in the bilateral ventral flexor reflex tract (bVFRT) of the cat. Exp Brain Res 18:256–267
Shokunbi MT, Hrycyshyn AW, Flumerfelt BA (1985) Spinal projections to the lateral reticular nucleus in the rat: a retrograde labelling study using horseradish peroxidase. J Comp Neurol 239:216–226
Shokunbi MT, Hrycyshyn AW, Flumerfelt BA (1986) An HRP study of the rubral and cortical afferents to the lateral reticular nucleus in the rat. J Comp Neurol 248:441–454
Trojanouski JQ, Schmidt ML (1984) Interneuronal transfer of axonally transported proteins: studies with HRP and HRP conjugates of wheat germ agglutinin, cholera toxin and the B subunit of cholera toxin. Brain Res 311:366–369
Tsukahara N, Bando T, Murakami F, Oda Y (1983) Properties of cerebello-precerebellar reverberating circuits. Brain Res 274:249–259
Venegas H, Hollander H, Distel HJ (1978) Early stages of uptake and transport of horseradish peroxidase by cortical structures, and its use for the study of local neurons and their processes. J Comp Neurol 177:193–212
Walberg J (1958a) Descending connections to the lateral reticular nucleus. An experimental study in the cat. J Comp Neurol 109:363–389
Walberg J (1958b) On the termination of the rubrobulbar fibres. Experimental observations in the cat. J Comp Neurol 110:65–73
Walberg F, Pompeiano O (1960) Fastigiofugal fibres to the lateral reticular nucleus; an experimental study in the cat. Exp Neurol 2:40–53
Westman J, Danckwardt-Lillieström N, Dietrichs E, Svensson BA, Walberg F (1986) Ultrastructure of spinal efferents to the lateral reticular nucleus: an EM study using anterograde transport of WGA-HRP complex. J Comp Neurol 246:301–311
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Rajakumar, N., Hrycyshyn, A.W. & Flumerfelt, B.A. Afferent organization of the lateral reticular nucleus in the rat: An anterograde tracing study. Anat Embryol 185, 25–37 (1992). https://doi.org/10.1007/BF00213598
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DOI: https://doi.org/10.1007/BF00213598