Summary
Efferents originating from the rat medial prefrontal cortex and projecting to diencephalic and mesencephalic structures were analyzed electrophysiologically. The antidromic activation technique was used in order to identify cortical neurons which innervate the medio-dorsal nucleus of the thalamus (MD), lateral habenula, ventro-medial mesencephalic tegmentum (VMT), substantia nigra (SN), superior colliculus (SC) and central gray (CG). Corresponding cortical neurons, found mainly in layers V and VI, were distributed in the rostro-caudal extension of the medial prefrontal cortex. Their conduction velocities were relatively slow and ranged between 0.4 and 5.5 m/s. The reciprocal collision test allowed us to determine whether a given cortical neuron innervated only one structure or whether it sent axon collaterals to other subcortical areas. Twelve patterns of axonal branching were established: MD-VMT, MD-SN, MD-SC, VMT-SN, VMT-SC, VMT-CG, SN-SC, habenula-VMT, habenula-CG, MD-SN-SC, VMT-SN-SC and VMT-habenula-CG. Finally, it was estimated that a large proportion of the prefrontal cells which project to a given subcortical structure also innervate one or two other subcortical areas. Results are discussed in the light of anatomical data and their functional significance.
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References
Afifi AK, Bahuth NB, Kaelber WW, Mikhael E, Nassar S (1974) The cortico-nigral fibre tract: An experimental Fink-Heimer study in cats. J Anat 118: 469–476
Akert K (1964) Comparative anatomy of frontal cortex and thalamo-frontal connections. In: Warren JM, Akert K (eds) The frontal granular cortex and behavior. McGraw Hill, New York, pp 372–396
Albe-Fessard D, Stutinsky F, Libouban S (1966) Atlas stéréotaxique du rat blanc. Edition CNRS, Paris
Beckstead RM (1979) An autoradiographic examination of cortico-cortical and subcortical projections of the medio-dorsal projection (prefrontal) cortex in the rat. J Comp Neurol 184: 43–62
Berger B, Thierry AM, Tassin JP, Moyne MA (1976) Dopaminergic innervation of the rat prefrontal cortex: A fluorescence histochemical study. Brain Res 106: 133–145
Brozoski IJ, Brown RM, Rosvold HE, Goldman PS (1979) Cognitive deficit caused by regional depletion of DA in prefrontal cortex of rhesus monkey. Science 205: 929–931
Bunney BS, Aghajanian GK (1976a) The precise localization of nigral afferents in the rat as determined by a retrograde tracing technique. Brain Res 117: 423–425
Bunney BS, Aghajanian GK (1976b) DA and NA innervated cells in the rat prefrontal cortex. Pharmacological differentiation using microiontophoretic techniques. Life Sci 19: 1783–1792
Catsman-Berrevoets CE, Kuypers HGJM (1981) A search for cortico-spinal collaterals to thalamus and mesencephalon by means of multiple retrograde fluorescent tracers in cat and rat. Brain Res 218: 15–33
Chevalier G, Deniau JM, Thierry AM, Féger J (1981) The nigrotectal pathway, an electrophysiological reinvestigation in the rat. Brain Res 213: 253–263
Deniau JM, Hammond C, Riszk A, Feger J (1978) Electrophysiological properties of identified output neurons of the rat substantia nigra (pars compacta and pars reticulata): Evidences for the existence of branched neurons. Exp Brain Res 32: 409–422
Divac I, Björklund A, Lindvall O, Passingham RE (1978) Converging projections from the mediodorsal thalamic nucleus and mesencephalic DA neurons to the neocortex in three species. J Comp Neurol 180: 59–72
Gerfen CR, Staines WA, Arbuthnott GW, Fibiger H (1982) Crossed connections of the substantia nigra in the rat. J Comp Neurol 207: 283–303
Greatex RM, Phillipson OT (1982) Demonstration of synaptic input from prefrontal cortex to the habenula in the rat. Brain Res 238: 192–197
Hardy SGP, Leichnetz GR (1981) Frontal cortical projections to the periaqueductal gray in the rat: A retrograde and orthograde horseradish peroxidase study. Neurosci Lett 23: 13–17
Jacobson S, Trojanowski J (1975) Corticothalamic neurons and thalamocortical terminal fields: An investigation in rat using horseradish peroxidase and autoradiography. Brain Res 85: 385–401
König JFR, Klippel RA (1963) The rat brain: A stereotaxic atlas of the forebrain and lower parts of brain stem. Williams and Wilkins, Baltimore
Krettek JE, Price JL (1977) Cortical projections of the mediodorsal nucleus and adjacent thalamic nuclei in the rat. J Comp Neurol 171: 157–192
Leichnetz GR, Astruc J (1976) The efferent projections of the medial prefrontal cortex in the squirrel monkey (saimiri sciureus). Brain Res 109: 455–472
Leichnetz GR, Spencer RF, Hardy SGP, Astruc J (1981) The prefrontal corticotectal projection in the monkey: An anterograde and retrograde horseradish peroxidase study. Neuroscience 6: 1023–1041
Leonard CM (1969) The prefrontal cortex of the rat. I. Cortical projection of the medio-dorsal nucleus. II. Efferent connections. Brain Res 12: 321–343
Leonard CM (1972) The connections of the dorsomedial nuclei. Brain Behav Evol 6: 524–541
Nauta WJH (1964) Some efferent connections of the prefrontal cortex in the monkey. In: Warren JM, Akert K (eds) The frontal granular cortex and behavior. McGraw-Hill, New York, pp 397–409
Phillipson OT (1979) Afferent projections to the ventral tegmental area of tsai and interfascicular nucleus: A horseradish peroxidase study in the rat. J Comp Neurol 187: 117–144
Pycock CJ, Carter CJ, Kerwin RW (1980) Effect of 6-hydroxydopamine lesions of the medial prefrontal cortex on neurotransmitter systems in subcortical sites in the rat. J Neurochem 34: 91–99
Rinvik E, Walberg F (1969) Is there a corticonigral tract? A comment based on experimental electron microscope observations in the cat. Brain Res 14: 742–744
Rose JE, Woolsey CN (1948) The orbitofrontal cortex and its connections with the mediodorsal nucleus in rabbit, sheep and cat. Res Publ Assoc Nerv Ment Dis 27: 210–232
Schlag J (1978) Electrophysiological mapping techniques. In: Robertson RT (ed) Methods in physiological psychology, vol II. Neuroanatomical research techniques. Academic Press, London New York, pp 385–404
Shinoda Y, Arnold AP, Asanuma H (1976) Spinal branching of corticospinal axons in the cat. Exp Brain Res 26: 215–234
Siegel A, Fukushima T, Meibach R, Burke L, Edinger H, Weiner S (1977) The origin of the afferent supply to the mediodorsal thalamic nucleus: Enhancement of HRP transport by selective lesions. Brain Res 135: 11–23
Simon H (1981) Neurones dopaminergiques A10 et système frontal. J Physiol (Paris) 77: 81–95
Thierry AM, Deniau JM, Féger J (1979) Effects of stimulation of the frontal cortex on identified output VMT cells in the rat. Neurosci Lett 15: 103–107
Usunoff KG, Romansky KV, Malinov GB, Ivanov DP, Blagov ZA, Galabov GP (1982) Electron microscopic evidence for the existence of a corticonigral tract in the cat. J Hirnforsch 23: 23–29
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Supported by grants from INSERM, DRET (81.050) and Rhône Poulenc SA
Recipient of fellowship from the Fonds de la Recherche en Santé du Quebec
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Thierry, A.M., Chevalier, G., Ferron, A. et al. Diencephalic and mesencephalic efferents of the medial prefrontal cortex in the rat: Electrophysiological evidence for the existence of branched axons. Exp Brain Res 50, 275–282 (1983). https://doi.org/10.1007/BF00239191
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DOI: https://doi.org/10.1007/BF00239191