2000 Fiscal Year Annual Research Report

脳内血糖センサーの局在と血糖センシングメカニズム

Research Project

Project/Area Number	10460131
Research Institution	Nagoya University
Principal Investigator	前多敬一郎名古屋大学, 大学院・生命農学研究科, 助教授 (30181580)
Keywords	ブドウ糖 / 血糖 / 細胞内カルシウム / 上衣細胞 / 延髄 / グルコキナーゼ / グルコースセンサー / グルコーストランスポーター
Research Abstract	低栄養による性腺機能の低下、さらにはそれに伴う繁殖率の低下は畜産業の中で大きな問題の一つである。特に高泌乳牛に多発する分娩後の排卵遅延、あるいは発展途上国における性成熟の遅延などは、もっとも大きな要素として低栄養が考えられてきた。申請者らのグループはこれまで絶食ラットを低栄養による生殖機能抑制のモデルとして、その神経内分泌メカニズムを明らかにする過程で、血糖利用性の低下が生殖機能を抑制する上でもっとも大きな因子であるとの考えに至った。申請者らは2-deoxyglucose(2DG)を用いた薬理学的血糖利用阻害により、血糖利用性の低下は、特異的なセンサーと神経経路により、性腺機能を抑制しているものと考えるにいたった。申請者は、β細胞における血糖センシングの中核をなすと考えられているGLUT2とglucokinaseが上衣細胞とセロトニンニューロンに局在することを明らかにした。本年度はこれらの細胞のグルコース感知能力の有無を調べるため、細胞内カルシウムを指標としたin vitroの実験を行った。血糖感知細胞を直接同定するため、成熟ラットから切り出した脳室上衣細胞およびA1/C1領域の細胞を酵素によりバラバラにした後、数時間の短期間培養を行い、高グルコースあるいは低グルコース条件下における細胞内カルシウムの変動を画像解析により検討した。その結果、glucokinase陽性細胞のほとんどが低グルコース刺激に反応することを見出し、これらの細胞が血糖センサーとして機能していることを示した。

Research Products

(18 results)

All Other

All Publications (18 results)

[Publications] Tsukahara,S.: "Effect of corticotropin-releasing hormone antagonist on oestrogen-dependent glucoprivic suppression of luteinizing hormone secretion in female rats."Journal of Neuroendocrinology. 11. 101-105 (1999)
[Publications] Tsukahara,S.: "Morphological characterization of relationship between gap junctions and gonadotropin-releasing hormone nerve terminals in the rat median eminence."Neurosicience Letters. 261. 105-108 (1999)
[Publications] Maekawa,F.: "Prevention of inhibitory effect of dorsal raphe nucleus lesioins on ovulation and LH surge by 5-HT 2A/2C receptor agonists in female rats."Neuroscience Research. 35. 291-298 (1999)
[Publications] Maekawa,F.: "Localization of glucokinase-like immunoreactivity in the rat lower brainstem : A possibility to the brain glucose-sensing mechanism."Endocrinology. 141. 375-384 (2000)
[Publications] Bucholtz,D.: "Regulation of pulsatile luteinizing hormone secretion by insulin in developing diabetic sheep."Biology of Reproduction. 62. 1248-1255 (2000)
[Publications] Tanaka,T.: "Central action of insulin regulates pulsatile luteinizing hormone secretion in the diabetic sheep."Biology of Reproduction. 62. 1256-1261 (2000)
[Publications] Tsukamura,H.: "Peripheral or central administration of motilin suppresses LH release in female rats : a novel role for motilin."Journal of Neuroendocrinology. 12. 403-408 (2000)
[Publications] Tsukamura,H.: "Intracerebroventricular administration of melanin-concentrating hormone suppresses pulsatile luteinizing hormone release in the female rat."Journal of Neuroendocrinology. 12. 529-534 (2000)
[Publications] Ichihara,G.: "Reproductive toxicity of 1-bromopropane, a newly introduced alternative to ozone-layer depleting solvents, in male rats."Toxicological Sciences. 54. 416-423 (2000)
[Publications] Tsukamura,H.: "Fasting-induced changes in pulsatile luteinizing hormone (LH) secretion in male rats : the role of testosterone and the hypothalamic paraventricularnudeus."Journal of Reproduction and Development. 46. 227-234 (2000)
[Publications] Ohkura,S.: "Central, but not peripheral, glucose-sensing mechanisms mediate glucoprivic suppression of pulsatile luteinizing hormone secretion in sheep."Endocrinology. 141. 4472-4480 (2000)
[Publications] Reyes,B.A.S.: "Effect of fasting on c-fos expression in the hypothalamic nuclei and nucleus ot the solitary tract in male rats : Time course study and the role of testosterone."Journal of Reproduction and Development. 47. 53-62 (2001)
[Publications] Reyes,B.A.S.: "Glucoprivation increases estrogen receptor-immunoreactivity in the brain catecholaminergic neurons in ovariectomized rats."Neuroscience Letters. 299. 109-112 (2001)
[Publications] Tsukamura.H.: "Non-metabolic and metabolic factors causing the lactational anestrus : rat models uncovering the neuroendocrine mechanism underlying the suckling-induced changes in the mother."Progress in Brain Research. (印刷中). (2001)
[Publications] Maeda,K.-I.: "Handbook of Experimental Animals, The Laboratory Rat"Academic Press. 756 (2000)
[Publications] Ohkura,S.: "Handbook of Experimental Animals, The Laboratory Rat"Academic Press. 756 (2000)
[Publications] 束村博子: "からだの中からストレスをみる"学会出版センター. 212 (2000)
[Publications] Tsukamura,H.: "Neuroplasticity Development & Steroid Hormone Action"CRC Press(印刷中). (2001)

2000 Fiscal Year Annual Research Report

脳内血糖センサーの局在と血糖センシングメカニズム

Principal Investigator

前多 敬一郎 名古屋大学, 大学院・生命農学研究科, 助教授 (30181580)

Research Products

[Publications] Tsukahara,S.: "Effect of corticotropin-releasing hormone antagonist on oestrogen-dependent glucoprivic suppression of luteinizing hormone secretion in female rats."Journal of Neuroendocrinology. 11. 101-105 (1999)

[Publications] Tsukahara,S.: "Morphological characterization of relationship between gap junctions and gonadotropin-releasing hormone nerve terminals in the rat median eminence."Neurosicience Letters. 261. 105-108 (1999)

[Publications] Maekawa,F.: "Prevention of inhibitory effect of dorsal raphe nucleus lesioins on ovulation and LH surge by 5-HT 2A/2C receptor agonists in female rats."Neuroscience Research. 35. 291-298 (1999)

[Publications] Maekawa,F.: "Localization of glucokinase-like immunoreactivity in the rat lower brainstem : A possibility to the brain glucose-sensing mechanism."Endocrinology. 141. 375-384 (2000)

[Publications] Bucholtz,D.: "Regulation of pulsatile luteinizing hormone secretion by insulin in developing diabetic sheep."Biology of Reproduction. 62. 1248-1255 (2000)

[Publications] Tanaka,T.: "Central action of insulin regulates pulsatile luteinizing hormone secretion in the diabetic sheep."Biology of Reproduction. 62. 1256-1261 (2000)

[Publications] Tsukamura,H.: "Peripheral or central administration of motilin suppresses LH release in female rats : a novel role for motilin."Journal of Neuroendocrinology. 12. 403-408 (2000)

[Publications] Tsukamura,H.: "Intracerebroventricular administration of melanin-concentrating hormone suppresses pulsatile luteinizing hormone release in the female rat."Journal of Neuroendocrinology. 12. 529-534 (2000)

[Publications] Ichihara,G.: "Reproductive toxicity of 1-bromopropane, a newly introduced alternative to ozone-layer depleting solvents, in male rats."Toxicological Sciences. 54. 416-423 (2000)

[Publications] Tsukamura,H.: "Fasting-induced changes in pulsatile luteinizing hormone (LH) secretion in male rats : the role of testosterone and the hypothalamic paraventricularnudeus."Journal of Reproduction and Development. 46. 227-234 (2000)

[Publications] Ohkura,S.: "Central, but not peripheral, glucose-sensing mechanisms mediate glucoprivic suppression of pulsatile luteinizing hormone secretion in sheep."Endocrinology. 141. 4472-4480 (2000)

[Publications] Reyes,B.A.S.: "Effect of fasting on c-fos expression in the hypothalamic nuclei and nucleus ot the solitary tract in male rats : Time course study and the role of testosterone."Journal of Reproduction and Development. 47. 53-62 (2001)

[Publications] Reyes,B.A.S.: "Glucoprivation increases estrogen receptor-immunoreactivity in the brain catecholaminergic neurons in ovariectomized rats."Neuroscience Letters. 299. 109-112 (2001)

[Publications] Tsukamura.H.: "Non-metabolic and metabolic factors causing the lactational anestrus : rat models uncovering the neuroendocrine mechanism underlying the suckling-induced changes in the mother."Progress in Brain Research. (印刷中). (2001)

[Publications] Maeda,K.-I.: "Handbook of Experimental Animals, The Laboratory Rat"Academic Press. 756 (2000)

[Publications] Ohkura,S.: "Handbook of Experimental Animals, The Laboratory Rat"Academic Press. 756 (2000)

[Publications] 束村博子: "からだの中からストレスをみる"学会出版センター. 212 (2000)

[Publications] Tsukamura,H.: "Neuroplasticity Development & Steroid Hormone Action"CRC Press(印刷中). (2001)

前多敬一郎名古屋大学, 大学院・生命農学研究科, 助教授 (30181580)