Aging of the Intrinsic Laryngeal Muscles

• Nishida Naoya

  Department of Otolaryngology, Ehime University School of Medicine

Bibliographic Information

Other Title

• ラット内喉頭筋の加齢変化―筋線維，筋線維構成タンパク，神経下装置の解析
• ラット内喉頭筋の加齢変化─筋線維,筋線維構成タンパク,神経下装置の解析
• ラット ナイコウトウキン ノ カレイ ヘンカ キン センイ キン センイ コウセイ タンパク シンケイカ ソウチ ノ カイセキ

Abstract

Aging of the intrinsic laryngeal muscles was investigated in rats by comparing adult and aged animals concerning the number and diameter of the muscle fibers, composition of the myosin heavy chain (MHC), and configuration of the subneural apparatus. Wistar strain rats of 24 months in age were subjected to this experiment as aged animals, while those of 10 to 17 weeks in age were used as the adult control. Histological study showed that in the aged animals the number and diameter of muscle fibers significantly decreased in the cricothyroid (CT) muscle. In the thyroarytenoid (TA) muscle, the number decreased but the diameter remained unchanged. Such changes were not observed in the posterior cricoarytenoid (PCA) muscle. Electrophoretic analysis of the MHCs of the CT muscle proved that the percentage of type IIB decreased and that of type IIA increased with aging. In the TA and PCA muscles, MHC composition did not undergo such change. Configurations of the subneural apparatus in these muscles were observed with a scanning electron microscope. In the aged animals, the labyrinthine type of primary synaptic clefts decreased and the depression type increased in the CT muscle. In contrast, such changes were not recognized in the TA or PCA muscles. In some thin muscle fibers of the aged animals, immature subneural apparatuses were identified exclusively in the CT muscles. These fibers were considered to be in a regenerative process for remodeling.<br>The present findings indicated that aging of the laryngeal muscles is prominent in the CT muscles, while the TA and PCA muscles are resistive to the aging process. This may reflect the difference in the role of laryngeal function : CT muscles control the tension of the vocal folds, while TA and PCA muscles control airway ventilation and swallowing, which are of vital importance.

Journal

• Nihon Kikan Shokudoka Gakkai Kaiho

  Nihon Kikan Shokudoka Gakkai Kaiho 59 (3), 318-329, 2008

  The Japan Broncho-esophagological Society

Keywords

• intrinsic laryngeal muscle
• aging
• scanning electron microscopy
• subneural apparatus
• myosin heavy chain

Details

• CRID: 1390001205012906880
• NII Article ID: 130004469955
• NII Article ID: 10021300801
• NII Book ID: AN00187474
• DOI: 10.2468/jbes.59.318
• ISSN: 18806848
• ISSN: 00290645
• NDL BIB ID: 9544134
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I9544134
• Web Site: https://search.jamas.or.jp/link/ui/2008229398
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed