Effects of Brain Grafts on Growth and Neuroendocrinological Abnormalities in Neonatally Monosodium Glutamate-Treated rats

• Project/Area Number: 63570530
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: 内分泌・代謝学
• Research Institution: FUKUI MEDICAL SCHOOL
• Principal Investigator: MIYABO Susumu FUKUI MEDICAL SCHOOL, Vice President, 副学長 (70019884)
• Co-Investigator(Kenkyū-buntansha): HAYASHI Takio FUKUI MEDICAL SCHOOL, Assistant, 医学部, 助手 (00198847) ; OOYA Eiichi FUKUI MEDICAL SCHOOL, Assistant, 医学部, 助手 (60160636) ; KISHIDA Shigeru FUKUI MEDICAL SCHOOL, Lecturer, 医学部, 講師 (90019589)
• Project Period (FY): 1988 – 1989
• Project Status: Completed (Fiscal Year 1989)
• Budget Amount: ¥2,000,000 (Direct Cost: ¥2,000,000); Fiscal Year 1989: ¥400,000 (Direct Cost: ¥400,000); Fiscal Year 1988: ¥1,600,000 (Direct Cost: ¥1,600,000)
• Keywords: MSG syndrome / Brain transplantation / ARC / GH-Surge / Lee-Index / 成長障害 / 視床下部ホルモン

Research Abstract

Administration of monosodium glutamate (MSG) to neonatal rats produces stunted growth, obesity and a number of metabolic/endocrinological abnormalities (MG-syndrome). In this research, the effects of implantation of normal fetal hypothalamic tissues containing the arcuate nuclei(ARC) on the MSG-syndrome. The ARC areas obtained from fetal rats were transplanted into the third ventricle of the 14-day old MSG-treated rats. Results. 1. In addition to the well-known severe damage in the ARC, the volumes of suprachiasmatic nuclei and ventromedial nuclei were also reduced in the MSG-treated rats. Histologically, the ingrowth of the grafts into the periventiricular zone was noted. 2. In the MSG-treated rats, the responses of pituitary hormones (GH.PRL,TSH.LH and ACTH) to their respective releasing hormones were similar among the intact, MSG-treated and MSG-treated/ARC-implatited rats, except FSH which was low, subnormally responded to GnRH in the MSG-treated rats and parially recovered by the grafting. 3. MSG treatment completely abolished the pulsatile GH secretion observed in the intact rats and the implantation of fetal ARC areas partially restored the episodic GH-surge. 4. In the MSG-treated rats, the basal blood glucose and serum insulin levels were high and their responses to oral glucose load were exaggerated. The brain grafts further enhanced the insulin response. 5. The Lee (obesity) index was uniformly high in the MSG-treated rats, whereas the subsequent ngbral transplants reduced the index to a normal range in about a half of the animals.

Research Products

• [Publications] Nakai,T.,Hayashi,S.,Tamai,T.,Takahashi,S.,Maeda,H.,and Miyabo,S: "Plasma lipoprotein metabolism in monosodium glutamate-induced obese rats" from “The International Symposium on PATHOGENESIS AND TREATMENT OF TYPE II DIABETES MELLITUS in Osaka,1987". 1. 142-150 (1987)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Miyanaga,K.,Miyabo,S.,and Ooya,E.: "Effect of chronic intracerebroventricular infusion of cortiocotropin-releasing factor on circadian plasma corticosterone rhythm in the rats" Endocrinoligia Japonica. 37. (1990)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Miyanaga,K.,Miyabo,S.,and Ooya,E.: "Negative feedback by corticosterone is the major mechanism responsible for corticotropin-releassing factor-induced desensitization" Journal of Neuroendocrinology. 2. (1990)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Miyabo,S.,Ooya,E.Miyanaga,K.,Kishida,S.,Aoyagi,N.,and Hirai,M: "Transplantation of arcuate nuclei areas improves neuroendo-crinological abnormalities induced by neonatal monosodium glutamate treatment"
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Nakai, T., Hayashi, S., Tamai, T., Takahashi, S., Maeda, H. and Miyabo, S.: "Plasma lipoprotein metabolism in monosodium glutamate-induced obese rats." International symposium on pathogenesis and treatment of type II diabetes mellitus in Osaka, pp142-150, 1988.
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Miyanaga, K., Miyabo, S. and Ooya, E.: "Effect of chronic intracerebroventricular infusion of corticotropin-releasing factor in circadian plasma corticosteron rhythm in the rats." Endocrinologia Japonica.
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Miyanaga, K., Miyabo, S. and Ooya, E.: "Negative feedback by corticosterone is the major mechanism responsible for corticosterone-releasing factor-induced desensitization." Journal of neuroendocinology.
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Miyabo, S., Ooya, E., Miyanaga, K., Kishida, S., Aoyagi, N. and Hirai, M.: "Transplantation of arcuate nuclei areas improves neuroendocrinological abnormalities induced by neonatal monosodium glutamate treatment."
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Nakai,t.,Hayashi,S.,Tamai,T.,Takahashi,S.,Maeda,H.and Miyabo,S: "Plasma lipoprotein metabolism in monosodium glutamate-induced obese rats" from “The International Symposium on PATHOGENESIS AND TREATMENT OF TYPE II DIABETES MELLITUS in Osaka,1987". 1. 142-150 (1987)
• [Publications] Miyanaga,K.,Miyabo,S.,and Ooya,E.: "Effect of chronic intracerebroventricular infusion of corticotropir -releasing factor on circadian plasma corticosterone rhythm in the rats" Endocrinologia Japonica. 37. (1990)
• [Publications] Miyanaga,K.,Miyabo,S.,and Ooya,E.: "Negative feedback by corticosterone is the major mechanism responsible for corticotropin-releasing factor-induced desensitization" Journal of Neuroendocrinology. 2. (1990)
• [Publications] Miyabo,S.,Ooya,E.,Miyanaga,K.,Kishida,S.,Aoyagi,N.and Hirai,M.: "Transplantation of arcuate nuclei areas improves neuroendo crinological abnormalities induced by neonatal monosodium glutamate treatment"
• [Publications] 宮保進: 日本内分泌学会雑誌.