Development of Vasoactive Intestinal Polypeptide-Immunoreactive Nerves in the Major Cerebral Arteries of the Quail Anterior Circulation

Andō, Kōichi; Mitsuiki, Shinji; Itoh, Katsuhito; Kusaba, Haruo; Soh, Tomoki; Tsukise, Azuma

doi:10.1292/jvms.001643

Cited by 1 publication

(2 citation statements)

References 11 publications

(23 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previous studies have shown that laminar flow with consistent and relatively high velocity is required to maintain the integrities of the arterial wall, 7 – 13 where the arterial endothelial cells play an essential role as a mechanoreceptors 14 – 21 of flow velocity by detecting wall shear stress (WSS). 22 – 26 A certain level of WSS is necessary for stimulating atheroprotective pathways by controlling various chemical mediators. 14 – 21 , 27 A high oscillatory shear index (OSI) that reflects fluctuations in WSS induces an inflammatory response, including an increase in reactive oxygen species.…”

Section: Introductionmentioning

confidence: 99%

“…6 Previous studies have shown that laminar flow with consistent and relatively high velocity is required to maintain the integrities of the arterial wall, [7][8][9][10][11][12][13] where the arterial endothelial cells play an essential role as a mechanoreceptors [14][15][16][17][18][19][20][21] of flow velocity by detecting wall shear stress (WSS). [22][23][24][25][26] A certain level of WSS is necessary for stimulating atheroprotective Y. Takehara et al pathways by controlling various chemical mediators.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Abnormal Flow Dynamics Result in Low Wall Shear Stress and High Oscillatory Shear Index in Abdominal Aortic Dilatation: Initial <i>in vivo</i> Assessment with 4D-flow MRI

Takehara

Isoda

Takahashi

et al. 2020

MRMS

View full text Add to dashboard Cite

Purpose: To characterize the non-laminar flow dynamics and resultant decreased wall shear stress (WSS) and high oscillatory shear index (OSI) of the infrarenal abdominal aortic dilatation, cardiac phase-resolved 3D phase-contrast MRI (4D-flow MRI) was performed. Methods: The prospective single-arm study was approved by the Institutional Review Board and included 18 subjects (median 67.5 years) with the dilated infrarenal aorta (median diameter 35 mm). 4D-flow MRI was conducted on a 1.5T MRI system. On 3D streamline images, laminar and non-laminar (i.e., vortex or helical) flow patterns were visually assessed both for the dilated aorta and for the undilated upstream aorta. Cardiac phase-resolved flow velocities, WSS and OSI, were also measured for the dilated aorta and the upstream undilated aorta. Results: Non-laminar flow represented by vortex or helical flow was more frequent and overt in the dilated aorta than in the undilated upstream aorta ( P < 0.0156) with a very good interobserver agreement (weighted kappa: 0.82–1.0). The WSS was lower, and the OSI was higher on the dilated aortic wall compared with the proximal undilated segments. In mid-systole, mean spatially-averaged WSS was 0.20 ± 0.016 Pa for the dilated aorta vs. 0.68 ± 0.071 Pa for undilated upstream aorta ( P < 0.0001), and OSI on the dilated aortic wall was 0.093 ± 0.010 vs. 0.041 ± 0.0089 ( P = 0.013). The maximum values and the amplitudes of the WSS at the dilated aorta were inversely proportional to the ratio of dilated/undilated aortic diameter ( r = −0.694, P = 0.0014). Conclusion: 4D-flow can characterize abnormal non-laminar flow dynamics within the dilated aorta in vivo . The wall of the infrarenal aortic dilatation is continuously and increasingly affected by atherogenic stimuli due to the flow disturbances represented by vortex or helical flow, which is reflected by lower WSS and higher OSI.

show abstract