アブストラクト(23巻2号:神奈川歯学)

神奈川歯学

Japanese

Title : ラット咬筋における構成蛋白の生後発育変化
Subtitle : 原著
Authors : 不島健持, 鈴木祥井
Authors(kana) :
Organization : 神奈川歯科大学矯正学教室
Journal : 神奈川歯学
Volume : 23
Number : 2
Page : 181-193
Year/Month : 1988 / 9
Article : 原著
Publisher : 神奈川歯科大学学会
Abstract : 「緒言」不正咬合患者を扱う歯科矯正学においては, 診断および治療を進めるうえで, 咬合系に対する配慮はもとより, その基盤をなす顎顔面頭蓋のパターンを把握することが重要である. この顎顔面頭蓋の成長発育は, 遺伝的要因に加え様々な環境的要因により制御されていると考えられており, 成長発育に関するいくつかの概念が提唱されるに至った. なかでも注目されるのはMossらによって展開されたfunctional matrix theoryで, これによると, "骨自体にはその成長の量や方向を調節するような決定要因はなく, 咀嚼筋などの機能的軟組織系こそ骨格系の成長を実際に支配している" とされている. このことは, 顎顔面頭蓋における骨格形態と機能との関係の基本概念として一般的に認められている. 一方, 現代人の食生活においては急激な軟食化が進行しており, 近年このような現象が顎顔面頭蓋の成長発育あるいは不正咬合の発現に何らかの影響を及ぼしている可能性について多大な関心が寄せられている.
Practice : 歯科学
Keywords : Rat Masseter Muscle, Myofibrillar Protein, Developmental Change, SDS-PAGE, Histone

English

Title : Developmental Changes of Myofibrillar Protein Composition in Rat Masseter Muscle
Subtitle : Original article
Authors : Kenji FUSHIMA, Yoshii Suzuki
Authors(kana) :
Organization : Department of Orthodontics, Kanagawa Dental College
Journal : Kanagawa Shigaku
Volume : 23
Number : 2
Page : 181-193
Year/Month : 1988 / 9
Article : Original article
Publisher : Kanagawa Odontological Society
Abstract : Abstract : It has been suggested that a fall in masticatory function by means of tendency to diet soft foods is related with the change in cranio-facial form and the appearance of malocclusion. Therefore, in order to examine the developmental changes of masticatory muscles in response to masticatory function during postnatal stage, the changes in myofibrillar protein compositions of rat masseter muscle were studied by using SDS-polyacrylamide gel and two dimensional gel electrophoresis. Comparing the compositions of crude myofibrillar proteins in the masseter muscle of adult and neonatal rats by SDS-polyacrylamide gel electrophoresis, marked differences were found in the bands migrated faster than actin, especially those from 30Kd to 43Kd and from 14.4Kd to 20Kd molecular weight. These differences were shown as different compositions of protein spots in both acidic and basic region of the electrophoretogram of two dimensional gel electrophoresis. It is known that myofibrillar proteins of skeletal muscle have multiple isoforms (fast type, slow type and etc.), which are dependent on muscle fiber type. Recent studies have demonstrated that these isoforms drastically changed according to the development of skeletal muscle. The differences found between adult and neonatal rats, however, were not depend on the changes in isoforms of myofibrillar proteins, because the protein composition of the neonatal masseter muscle was distinct from that of either the fast or slow skeletal muscles, and no isoform changes of myofibrillar proteins (myosin light chain, tropomyosin and troponin) were detected by two dimensional gel electrophoresis. During the postnatal development of rat masseter muscle, several myofibrillar proteins were altered, and the compositions of myofibrillar proteins observed in the neonatal masseter were gradually similar to that of adult type after 20 days. Noteworthy is the observation that the functional differentiation of masseter muscle has occured after 20 days by means of succinate dehydrogenase staining. Therefore, it is suggested that the developmental changes of protein compositions in masseter muscle related with the functional raising of masseter muscle caused by the change of feeding way from suckling to mastication. Proteins of rat masseter muscle migrated from 14.4Kd to 20Kd, which were gradually decreased in the early stage of development, were identified as nucleosome histones (H3, H2B, H2A and H4) by specific staining and AUT (acetic acid / urea / Triton X-100)-PAGE. It is considered that these histones play some roles in the maturation of masseter muscle during early period after birth.
Practice : Dentistry
Keywords : Rat Masseter Muscle, Myofibrillar Protein, Developmental Change, SDS-PAGE, Histone