ヒト橈骨動脈の圧 － 径関係の非侵襲計測法の確立とこれに対する平滑筋収縮状態の影響評価

抄録

A novel apparatus for non-invasive, in vivo evaluation of arterial mechanical properties was developed. A rigid airtight chamber with an ultrasound probe was attached to the forearm to manipulate transmural pressure (TP) of the radial artery by changing the pressure in the chamber. Pressure-diameter relationship of the radial artery was obtained by measuring the diameter with the probe while pressurizing and depressurizing the chamber. Pressure-diameter relationship of the radial artery could be obtained reproducibly over a wide range of TP. Contrary to intuition, the diameter decreased and increased when TP increased and decreased, respectively, in some TP ranges. This phenomenon disappeared when pressur-diameter relationship was obtained after taking alcohol, indicating that it was caused by the myogenic response of smooth muscle cells.This apparatus may be useful to measure not only pressure-diameter relationship but also contractility of smooth muscle cell.