Pharmacology Laboratory, Molecular Function and Pharmacology Laboratories, Taisho Pharmaceutical Co., Ltd, Saitama, Japan.
Br J Pharmacol. 2010 Nov;161(6):1391-402. doi: 10.1111/j.1476-5381.2010.00973.x.
20-Hydroxyeicosatetraenoic acid is a potent vasoconstrictor that contributes to cerebral ischaemia. An inhibitor of 20-Hydroxyeicosatetraenoic acid synthesis, TS-011, reduces infarct volume and improves neurological deficits in animal stroke models. However, little is known about how TS-011 affects the microvessels in ischaemic brain. Here, we investigated the effect of TS-011 on microvessels after cerebral ischaemia.
TS-011 (0.3 mg·kg(-1) ) or a vehicle was infused intravenously for 1 h every 6 h in a mouse model of stroke, induced by transient occlusion of the middle cerebral artery occlusion following photothrombosis. The cerebral blood flow velocity and the vascular perfusion area of the peri-infarct microvessels were measured using in vivo two-photon imaging.
The cerebral blood flow velocities in the peri-infarct microvessels decreased at 1 and 7 h after reperfusion, followed by an increase at 24 h after reperfusion in the vehicle-treated mice. We found that TS-011 significantly inhibited both the decrease and the increase in the blood flow velocities in the peri-infarct microvessels seen in the vehicle-treated mice after reperfusion. In addition, TS-011 significantly inhibited the reduction in the microvascular perfusion area after reperfusion, compared with the vehicle-treated group. Moreover, TS-011 significantly reduced the infarct volume by 40% at 72 h after middle cerebral artery occlusion.
These findings demonstrated that infusion of TS-011 improved defects in the autoregulation of peri-infarct microcirculation and reduced the infarct volume. Our results could be relevant to the treatment of cerebral ischaemia.
20-羟二十碳四烯酸是一种强效的血管收缩剂,可导致脑缺血。20-羟二十碳四烯酸合成抑制剂 TS-011 可减少动物中风模型的梗死体积并改善神经功能缺损。然而,对于 TS-011 如何影响缺血性脑内的微血管,目前知之甚少。在此,我们研究了 TS-011 在脑缺血后对微血管的影响。
采用光血栓形成后短暂性大脑中动脉闭塞法诱导中风小鼠模型,TS-011(0.3mg·kg(-1))或载体以每 6 小时静脉输注 1 小时的方式进行治疗。采用活体双光子成像测量梗死周边区微血管的脑血流速度和血管灌注面积。
在再灌注后 1 小时和 7 小时,再灌注后 24 小时,载体处理的小鼠中梗死周边区微血管的脑血流速度下降,随后增加。我们发现,TS-011 显著抑制了载体处理的小鼠再灌注后梗死周边区微血管血流速度的下降和增加。此外,与载体处理组相比,TS-011 显著抑制了再灌注后微血管灌注面积的减少。此外,TS-011 可使大脑中动脉闭塞 72 小时后的梗死体积减少 40%。
这些发现表明,TS-011 输注可改善梗死周边区微循环自动调节的缺陷,并减少梗死体积。我们的结果可能与脑缺血的治疗有关。