TY - GEN
T1 - Energetics in arterioles during nitric oxide dependent and independent vasodilation
AU - Shibata, Masahiro
AU - Yamakoshi, Takehiro
AU - Yamakoshi, Ken Ichi
PY - 2007/12/1
Y1 - 2007/12/1
N2 - The objective of this study was to evaluate whether the nitric oxide (NO) would decrease vessel wall oxygen consumption by decreasing the mechanical work of vascular smooth muscle. The oxygen consumption rate (QO2) of arteriolar walls in rat cremaster muscle was determined in vivo during NO dependent and -independent vasodilation based on the intra- and perivascular oxygen tension (PO2) measured by phosphorescence quenching technique. NO dependent vasodilation was induced by increased NO production due to increased blood flow, while NO independent vasodilation was induced by topical administration of papaverine. The energy efficiency was evaluated by the variable ratio of wall tension to QO2 between normal and vasodilated conditions. NO dependent and -independent dilation increased arteriolar diameters by 13% and 17%, respectively. Vascular wall QO2 decreased significantly during both dilations. There was no significant difference between the energy efficiency during NO dependent and -independent vasodilation, suggesting the decrease in vascular wall QO2 produced by NO to be related to a decrease in the mechanical work of vascular smooth muscle.
AB - The objective of this study was to evaluate whether the nitric oxide (NO) would decrease vessel wall oxygen consumption by decreasing the mechanical work of vascular smooth muscle. The oxygen consumption rate (QO2) of arteriolar walls in rat cremaster muscle was determined in vivo during NO dependent and -independent vasodilation based on the intra- and perivascular oxygen tension (PO2) measured by phosphorescence quenching technique. NO dependent vasodilation was induced by increased NO production due to increased blood flow, while NO independent vasodilation was induced by topical administration of papaverine. The energy efficiency was evaluated by the variable ratio of wall tension to QO2 between normal and vasodilated conditions. NO dependent and -independent dilation increased arteriolar diameters by 13% and 17%, respectively. Vascular wall QO2 decreased significantly during both dilations. There was no significant difference between the energy efficiency during NO dependent and -independent vasodilation, suggesting the decrease in vascular wall QO2 produced by NO to be related to a decrease in the mechanical work of vascular smooth muscle.
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U2 - 10.1109/IEMBS.2007.4352635
DO - 10.1109/IEMBS.2007.4352635
M3 - Conference contribution
C2 - 18002301
AN - SCOPUS:57649217298
SN - 1424407885
SN - 9781424407880
T3 - Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings
SP - 1695
EP - 1698
BT - 29th Annual International Conference of IEEE-EMBS, Engineering in Medicine and Biology Society, EMBC'07
T2 - 29th Annual International Conference of IEEE-EMBS, Engineering in Medicine and Biology Society, EMBC'07
Y2 - 23 August 2007 through 26 August 2007
ER -