Functional histology of the macula flava in the human vocal fold--Part 2: Its role in the growth and development of the vocal fold.
OBJECTIVE
This study aims to clarify the role of the maculae flavae (MFe) during growth and development of the human vocal fold mucosa (VFM).


METHODS
Our current results concerning the MFe in the human newborn, infant, and child VFM are summarized.


RESULTS
Newborns already had immature MFe at the same sites as adults. They were composed of dense masses of vocal fold stellate cells (VFSCs), whereas extracellular matrix components were sparse. VFSCs in the newborn MFe had already started synthesizing extracellular matrices (EM). During infancy, the EM synthesized in the MFe appeared in the VFM to initiate the formation of the three-dimensional extracellular matrix structure of the human VFM. During childhood, MFe including VFSCs continued to synthesize EM such as collagenous, reticular, and elastic fibers, and hyaluronic acid (glycosaminoglycan), which are essential for the human VFM as a vibrating tissue. The MFe in newborns, infants and children were related to the growth and development of the human VFM.


CONCLUSIONS
Human MFe including VFSCs were inferred to be involved in the metabolism of EM, essential for the viscoelasticity of the human VFM, and are considered to be an important structure in the growth and development of the human VFM.
Sato
Kiminori
K
Department of Otolaryngology-Head and Neck Surgery, Kurume University School of Medicine, Kurume, Japan. kimisato@oct-net.ne.jp
Umeno
Hirohito
H
Nakashima
Tadashi
T
D000328:Adult; D002648:Child; D004547:Elastic Tissue / Q000648:ultrastructure; D004548:Elasticity; D005109:Extracellular Matrix / Q000648:ultrastructure; D006025:Glycosaminoglycans / Q000032:analysis; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007820:Laryngeal Mucosa / Q000254:growth & development / Q000648:ultrastructure; D014783:Viscosity; D014827:Vocal Cords / Q000166:cytology / Q000254:growth & development / Q000648:ultrastructure*
D006025:Glycosaminoglycans