Myogenic response of umbilical atreries

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K10943
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Anesthesiology
• Research Institution: University of Miyazaki
• Principal Investigator: Isao Tsuneyoshi 宮崎大学, 医学部, 教授 (90301390)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 臍帯動脈 / 筋源性収縮反応 / 血管反応性 / NO / アドレノメデュリン

Outline of Final Research Achievements

Myogenic activation of vascular smooth muscle is the phenomenon underlying active force development in response to smooth-muscle stretch and/or increased pressure inside a blood vessel. It is considered, therefore, that myogenic responses may contribute to the control of organ blood flow. In the present investigation, we first discovered that the murine umbilical artery showed myogenicity in response to increased transmural pressure, suggesting that its myogenicity may be a component in fetoplacental blood flow autoregulation. These results suggest that the myogenic response is important in the physiological regulation of tone in murine umbilical arteries. Since the oscillations were inhibited by nifedipine and ryanodine, they were presumably at least partly dependent upon L-type Ca2+ channels and upon Ca2+ release from the sarcoplasmic reticulum.

Free Research Field

麻酔学

Academic Significance and Societal Importance of the Research Achievements

臍帯動脈における筋源性収縮反応を検討することは、ヒト母体の臍帯血流を考える上で貴重な資料と成り得る。本実験結果から、臍帯動脈は強い筋源性収縮反応を呈することで、母体の血圧変動に対し一定の血流を維持する自動制御機能として重要な機能を持つこと、さらにその機能はNOにより補正され、温度低下により機能が損なわれることが明らかになった。また手術時におけるアドレノメデュリンの測定結果から、アドレノメデュリンは手術侵襲に応じて分泌が増加し、生体反応に強く関与していることが示唆された。今後、アドレノメデュリンの役割に関する検討を推進していきたい。