title: Do palisade endings in extraocular muscles arise from neurons in the motor nuclei?
abstract: OBJECTIVE
  The purpose of this study was to localize the cell bodies of palisade endings that are associated with the myotendinous junctions of the extraocular muscles.
  
  
  METHODS
  Rhesus monkeys received tract-tracer injections (tetramethylrhodamine dextran [TMR-DA] or choleratoxin subunit B [CTB]) into the oculomotor and trochlear nuclei, which contain the motoneurons of extraocular muscles. All extraocular muscles were processed for the combined immunocytochemical detection of the tracer and SNAP-25 or synaptophysin for the visualization of the complete muscle innervation.
  
  
  RESULTS
  In all muscles--except the lateral rectus--en plaque and en grappe motor endings, but also palisade endings, were anterogradely labeled. In addition a few tracer-labeled tendon organs were found. One group of tracer-negative nerve fibers was identified as thin tyrosine hydroxylase-positive sympathetic fibers, and a second less numerous group of tracer-negative fibers may originate from the trigeminal ganglia. No cellular or terminal tracer labeling was present within the mesencephalic trigeminal nucleus or the trigeminal ganglia.
  
  
  CONCLUSIONS
  These results confirm those of earlier studies and furthermore suggest that the somata of palisade endings are located close to the extraocular motor nuclei--in this case, probably within the C and S groups around the periphery of the oculomotor nucleus. The multiple en grappe endings have also been shown to arise from these cells groups, but it is not possible to distinguish different populations in these experiments.
authors.affiliation: Institute of Anatomy I, Ludwig-Maximilian University of Munich, Munich, Germany.
authors.forename: Karoline
authors.initials: K
authors.lastname: Lienbacher
authors.forename: Michael
authors.initials: M
authors.lastname: Mustari
authors.forename: Howard S
authors.initials: HS
authors.lastname: Ying
authors.forename: Jean A
authors.initials: JA
authors.lastname: Büttner-Ennever
authors.forename: Anja K E
authors.initials: AK
authors.lastname: Horn
mesh_terms: D000818:Animals; D002772:Cholera Toxin / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D008253:Macaca mulatta; D009046:Motor Neurons / Q000166:cytology* / Q000378:metabolism; D009411:Nerve Endings / Q000378:metabolism*; D009412:Nerve Fibers / Q000378:metabolism*; D009469:Neuromuscular Junction / Q000166:cytology*; D009801:Oculomotor Muscles / Q000294:innervation* / Q000378:metabolism; D012235:Rhodamines / Q000378:metabolism; D016708:Synaptophysin / Q000378:metabolism; D050825:Synaptosomal-Associated Protein 25 / Q000378:metabolism; D013710:Tendons / Q000294:innervation
chemical_list: D012235:Rhodamines; D016708:Synaptophysin; D050825:Synaptosomal-Associated Protein 25; C005358:tetramethylrhodamine; D002772:Cholera Toxin