title: Functional histology of the macula flava in the human vocal fold--Part 1: its role in the adult vocal fold.
abstract: OBJECTIVE
  This study aims to clarify the role of the maculae flavae (MFe) in the human adult vocal fold mucosa (VFM).
  
  
  METHODS
  Our current results concerning MFe in the human adult VFM are summarized.
  
  
  RESULTS
  MFe were found to be composed of dense masses of vocal fold stellate cells (VFSCs) and extracellular matrices (EM), such as fibrous proteins and glycosaminoglycans, which are essential for the EM in the human VFM. VFSCs in the MFe demonstrated marked morphologic differences from conventional fibroblasts. They were irregular and stellate in shape and possessed slender cytoplasmic processes. They had well-developed intracellular organelles. A number of vesicles were present at the periphery of the cytoplasm. They constantly synthesized EM. The VFSCs possessed lipid droplets and stored vitamin A. VFSCs formed an independent cell category of cells in the human VFM. The VFSCs in aged adult MFe decreased their activity, and had abnormal metabolism.
  
  
  CONCLUSIONS
  Human MFe including VFSCs seem to be involved in the metabolism of EM which are essential for the viscoelasticity of the lamina propria of the VFM, and to be responsible for maintaining the characteristic layered structure of the human VFM. Age-related changes in VFSCs were found to influence the metabolism of EM in the VFM.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Kurume University School of Medicine, Kurume, Japan. kimisato @ oct-net.ne.jp
authors.forename: Kiminori
authors.initials: K
authors.lastname: Sato
authors.forename: Hirohito
authors.initials: H
authors.lastname: Umeno
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nakashima
mesh_terms: D000368:Aged; D000375:Aging / Q000378:metabolism / Q000473:pathology; D002452:Cell Count; D003593:Cytoplasm / Q000378:metabolism / Q000648:ultrastructure; D005109:Extracellular Matrix / Q000378:metabolism / Q000648:ultrastructure; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D007820:Laryngeal Mucosa / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D008055:Lipids; D008297:Male; D008855:Microscopy, Electron, Scanning; D015388:Organelles / Q000378:metabolism / Q000648:ultrastructure; D014801:Vitamin A / Q000378:metabolism; D014827:Vocal Cords / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D008055:Lipids; D014801:Vitamin A