アブストラクト(29巻2号:神奈川歯学)

神奈川歯学

Japanese

Title : ラット顎下腺の内分泌作用に関する研究 - 特に精巣ステロイド代謝に及ぼす影響 -
Subtitle : 原著
Authors : 山口賢治, 南田厳司, 加藤靖正, 小鹿真理, 中山義之
Authors(kana) :
Organization : 神奈川歯科大学生化学教室
Journal : 神奈川歯学
Volume : 29
Number : 2
Page : 105-112
Year/Month : 1994 / 9
Article : 原著
Publisher : 神奈川歯科大学学会
Abstract : 「緒言」 齧歯目顎下腺は, 上皮細胞成長因子(Epidermal growth factor; EGF)をはじめ, 種々の生理活性物質を産生分泌しており, アンドロゲン, プロゲスチン, 副腎皮質ホルモンは, この様なペプチドを増加させ, その結果血中の濃度を上昇させることが報告されている. 齧歯目顎下腺に含まれるこれらペプチドの生理的な意義については, 一義的な解釈はなされていないが, 顎下腺と雄生殖機能との関係について論じたものがある. つまり, 雄ラットの顎下腺摘出による生殖機能の変化に関する研究で, Boyerらは, 顎下腺摘出により精巣の重量は明らかに減少し, これは, 間質成分の萎縮によるものであると報告している. また, 電子顕微鏡による観察では, ラット・ライディッヒ細胞のミトコンドリアや細網構造の減少が示されている. Tsutsumiらは, EGFの精子産生過程における減数分裂への関与を指摘している.
Practice : 歯科学
Keywords : アンドロゲン, 顎下腺, ラット

English

Title : Study on Endocrine Action of Rat Submandibular Gland : Regulation of Steroidgenesis in Testis
Subtitle :
Authors : Kenji YAMAGUCHI, Genshi MINAMIDA, Yasumasa KATO, Shinri KOSHIKA, Yoshiyuki Nakayama
Authors(kana) :
Organization : Department of Biochemistry, Kanagawa Dental College
Journal : Kanagawa Shigaku
Volume : 29
Number : 2
Page : 105-112
Year/Month : 1994 / 9
Article : Original article
Publisher : Kanagawa Odontological Society
Abstract : Study on the androgen biosynthesis in rat testis after sialoadenectomy (extirpation of submandibular gland) is reported in this papar. Wistar rats were sialoadenectomized at 4,5,6,7,8 and 9 weeks of age. All rats were sacrificed at 10 weeks of age. The 14C-labeled substrate, pregenenolone, 17α-OH progesterone, or Δ4-androstenedione was incubated with testicular microsome in Tris-HCl buffer in the presence of NAD and NADPH. Sialoadenectomy was less effective on the 3β-hydroxysteroid dehydrogenase activity. The effects of sialoadenectomy on the androgen biosynthesis were revealed as the results of the decreased C17-20 lyase and enhanced 17β-hydroxysteroid dehydrogenase (17β-HSD). These variations were significant when the operation was carried out at prepubertal stage. Especially, the activity of C17-20 lyase was 27% of the control when the ectomy was done at 5 weeks of age, and the 17β-HSD activity was 2 times higher than control when at 4 weeks of age. The activities of C17-20 lyase and 17β-HSD were increased and decreased respectively in the dose dependent manner of the added submandibular gland extract (SMG extract) in the testicular microsome of rat sialoadenectomized at 6 weeks of age. When testicular cells were cultured in serum-free medium in the presence of Δ4-androstenedione for 3 days, the amount of the secreted testosterone (T) from the cells into the medium was not affected by the ectomy. However, while T secretion was increased by the SMG extract and not changed by LH or FSH in the testicular cell culture from control rats, the T secretion was not influenced by the SMG extract and enhanced by gonadotropins in the cells of sialoadenectomized rat testis. From the results, it was elucidated that rat submandibular gland had the regulatory function(s) on the androgen biosynthesis in the testis, by two actions, one is direct on the testis and the other is on pituitary.
Practice : Dentistry
Keywords :