PMID- 6876501
OWN - NLM
STAT- MEDLINE
DCOM- 19830923
LR  - 20190829
IS  - 0021-521X (Print)
IS  - 0021-521X (Linking)
VI  - 33
IP  - 2
DP  - 1983
TI  - Synaptic inputs of feline rubrospinal neurons from the parietal association
      cortex, pretectum and medial lemniscus, and their lesion-induced sprouting.
PG  - 197-214
AB  - Synaptic inputs of rubrospinal (RN) neurons from the cerebral cortex, pretectal
      area (PRT), and medial lemniscus (ML) were investigated electrophysiologically in
      the cat. Stimulation of the ipsilateral parietal association cortex (PASC) and
      secondary sensory area (SII) produced slow-rising about 3 msec rise time
      monosynaptic EPSPs which were, in some cases, followed by hyperpolarizations,
      similar to the sensorimotor cortex (SM)-induced PSPs previously observed.
      Stimulation of the contralateral cerebral cortex never produced detectable PSPs. 
      Topographical arrangement of PASC-rubral projection was found. Stimulation of the
      lateral part of PASC induced EPSPs predominantly in RN cells innervating the
      cervicothoracic spinal segments, while stimulation of the medial part of PASC
      produced EPSPs predominantly in RN cells innervating the lumbosacral cord.
      Furthermore, PASC-induced EPSPs were more frequently recorded at the rostral half
      of RN than at the caudal half. Monosynaptic EPSPs and multisynaptic IPSPs were
      induced by stimulation of the ipsilateral PRT and ML. PRT- and ML-induced EPSPs
      had times-to-peak of 1.0 +/- 0.4 msec (mean +/- S.D.) and 1.6 +/- 0.5 msec,
      respectively, which were intermediate to those of the cerebral peduncle (CP)- and
      nucleus interpositus of the cerebellum (IP)-induced EPSPs. Furthermore,
      sensitivity of amplitudes of PRT-induced EPSPs to membrane hyperpolarization was 
      intermediate to those of CP- and IP-EPSPs, and that of ML-induced EPSPs was lower
      than that of IP-EPSPs. Therefore, it is likely that synapses of PRT and ML fibers
      are formed between the distal dendrites where CP-rubral synapses terminate and
      soma where IP-rubral synapses terminate. PASC-induced EPSPs after chronic IP and 
      SM lesions had a new fast-rising component and the effectiveness of ML
      stimulation to induce the unit spike of RN cells was clearly increased in IP and 
      SM lesioned cats. It was suggested that PASC-rubral fibers sprouted and formed
      new synapses at the proximal portions of soma-dendritic membranes of RN cells
      after IP and SM destructions. Collateral fibers to RN cells of the pyramidal
      tract were also shown to sprout new synapses following IP and ML lesions.
FAU - Fujito, Y
AU  - Fujito Y
FAU - Maeda, J
AU  - Maeda J
FAU - Murakami, F
AU  - Murakami F
FAU - Tsukahara, N
AU  - Tsukahara N
LA  - eng
PT  - Journal Article
PL  - Japan
TA  - Jpn J Physiol
JT  - The Japanese journal of physiology
JID - 2985184R
SB  - IM
MH  - Animals
MH  - Brain Stem/*physiology
MH  - Cats
MH  - Denervation
MH  - Evoked Potentials
MH  - Mesencephalon/*physiology
MH  - Parietal Lobe/*physiology
MH  - Pyramidal Tracts/physiology
MH  - Red Nucleus/cytology/*physiology
MH  - Spinal Cord/cytology/*physiology
MH  - Synapses/*physiology
EDAT- 1983/01/01 00:00
MHDA- 1983/01/01 00:01
CRDT- 1983/01/01 00:00
PHST- 1983/01/01 00:00 [pubmed]
PHST- 1983/01/01 00:01 [medline]
PHST- 1983/01/01 00:00 [entrez]
AID - 10.2170/jjphysiol.33.197 [doi]
PST - ppublish
SO  - Jpn J Physiol. 1983;33(2):197-214. doi: 10.2170/jjphysiol.33.197.