Project/Area Number |
16580238
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Basic veterinary science/Basic zootechnical science
|
Research Institution | Gifu University |
Principal Investigator |
SHIINA Takahiko (2005-2006) Gifu University, Faculty of Applied Biological Sciences, Research Associate, 応用生物科学部, 助手 (90362178)
志水 泰武 (2004) 岐阜大学, 応用生物科学部, 助教授 (40243802)
|
Co-Investigator(Kenkyū-buntansha) |
椎名 貴彦 岐阜大学, 応用生物科学部, 助手 (90362178)
|
Project Period (FY) |
2004 – 2006
|
Project Status |
Completed (Fiscal Year 2006)
|
Budget Amount *help |
¥3,700,000 (Direct Cost: ¥3,700,000)
Fiscal Year 2006: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2005: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2004: ¥1,500,000 (Direct Cost: ¥1,500,000)
|
Keywords | Chicken / Diabetes mellitus / Glucose toxicity / Glucose tolerance test / Insulin resistance / Electrophysiology / Mesenteric artery / Purinergic neuron / 内皮細胞 / 血糖値 / インスリン / グルコース輸送体 |
Research Abstract |
Although fasting blood glucose level in birds is higher than that in mammals, which is over 300 mg/dl, glucose toxicity such as cardiovascular system and nervous system abnormality is not expressed. In this study, it was investigated whether blood glucose is regulated to high level actively. Glucose tolerance test was performed to measure the elimination of blood glucose in chickens, which showed that increased blood glucose level was reversed to the original level rapidly. This result suggests that blood glucose level in chickens might be regulated actively. However, glucose transporter type 4, which is essential for insulin effects in mammals, could not be detected in chicken skeletal muscle and adipose tissue. In addition, self-phosphorylation in insulin receptors and tyrosine phosphorylation in IRS1-4 in skeletal muscle after insulin injection did not occur. Thus, the down-regulation mechanism of blood glucose in chickens might be different from that in mammals essentially. Next, Vascular system, which is sensitive to glucose toxicity in mammals, was analyzed electrophysiologically. It was showed that chicken mesenteric artery longitudinal muscle is regulated by excitatory purinergic neurotransmission via P2Y receptors. In chicken mesenteric artery circular muscle, slow hyperpolarization was induced by the interaction of purinergic neurons and endothelium. In addition, neuronal control in chicken mesenteric artery longitudinal muscle changed according to maturing. These results suggest that neuronal regulation of vascular system in chickens might be different from that in mammals.
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