Functional response of cerebral blood flow induced by somatosensory stimulation in rats with subarachnoid hemorrhage
Functional response of cerebral blood flow induced by somatosensory stimulation in rats with subarachnoid hemorrhage
复制标题
体感刺激引起蛛网膜下腔出血大鼠脑血流的功能反应
DOI：
10.1117/1.jbo.20.9.096008
复制
发表时间：
2015
影响因子：
3.5
通讯作者：
Jinling Lu
中科院分区：
文献类型：
--
作者：
Zhiguo Li;Qin Huang;Peng Liu;Pengcheng Li;Lianting Ma;Jinling Lu
抽象。蛛网膜下腔出血（SAH）常伴有脑血管痉挛（CVS），CVS是脑大动脉狭窄的现象，继而可产生迟发性缺血性神经功能缺损（DIND）如偏侧感觉功能障碍。CVS被认为是SAH患者DIND的主要原因。然而，预防SAH后血管痉挛以改善预后的治疗可能并不总是有效。因此，寻找SAH后CVS与DIND之间关系的答案至关重要。SAH后局部脑血流量（CBF）在功能激活过程中的调节机制尚不清楚，而CBF的调节可能在减弱CVS对皮层功能的影响中发挥重要作用。因此，在蛛网膜下腔出血动物模型中评价脑血流在激活皮层的功能反应是值得的。目前，大多数SAH的效果评价是通过神经行为量表进行的。感觉刺激时皮层激活的功能成像可能比行为量表更有助于局部地反映躯体感觉皮层的功能。我们在大鼠蛛网膜下腔出血模型上，通过激光散斑成像研究了电刺激对侧前爪引起的体感皮层CBF的功能反应。对照组10只，蛛网膜下腔出血组9只。蛛网膜下腔出血（SAH）模型采用自体血经枕大池双重注射法。对照组采用相同的手术方法，不进行脑脊液抽吸或血液注射。SAH组CVS明显。SAH组大鼠脑血流反应峰值较对照组延迟，但相对变化幅度、持续时间及曲线下面积两组间无显著性差异。结果提示，SAH大鼠躯体感觉皮层局部脑血流对躯体感觉刺激引起的功能激活的调节功能可能未受到严重损害。因此，我们的研究结果可能有助于理解SAH患者即使发现CVS也可能不会发生DIND的临床现象。
Abstract. Subarachnoid hemorrhage (SAH) is often accompanied by cerebral vasospasm (CVS), which is the phenomenon of narrowing of large cerebral arteries, and then can produce delayed ischemic neurological deficit (DIND) such as lateralized sensory dysfunction. CVS was regarded as a major contributor to DIND in patients with SAH. However, therapy for preventing vasospasm after SAH to improve the outcomes may not work all the time. It is important to find answers to the relationship between CVS and DIND after SAH. How local cerebral blood flow (CBF) is regulated during functional activation after SAH still remains poorly understood, whereas, the regulation of CBF may play an important role in weakening the impact of CVS on cortex function. Therefore, it is worthwhile to evaluate the functional response of CBF in the activated cortex in an SAH animal model. Most evaluation of the effect of SAH is presently carried out by neurological behavioral scales. The functional imaging of cortical activation during sensory stimulation may help to reflect the function of the somatosensory cortex more locally than the behavioral scales do. We investigated the functional response of CBF in the somatosensory cortex induced by an electrical stimulation to contralateral forepaw via laser speckle imaging in a rat SAH model. Nineteen Sprague-Dawley rats from two groups (control group, n=10 and SAH group, n=9) were studied. SAH was induced in rats by double injection of autologous blood into the cisterna magna after CSF aspiration. The same surgical procedure was applied in the control group without CSF aspiration or blood injection. Significant CVS was found in the SAH group. Meanwhile, we observed a delayed peak of CBF response in rats with SAH compared with those in the control group, whereas no significant difference was found in magnitude, duration, and areas under curve of relative CBF changes between the two groups. The results suggest that the regulation function of local CBF during functional activation induced by somatosensory stimulation might not be seriously impaired in the somatosensory cortex of rats with SAH. Therefore, our findings might help to understand the clinical phenomenon that DIND might not occur even when CVS was found in SAH patients.