Belayev Ludmila, Saul Isabel, Curbelo Karell, Busto Raul, Belayev Andrey, Zhang Yongbo, Riyamongkol Panomkhawn, Zhao Weizhao, Ginsberg Myron D
Cerebral Vascular Disease Research Center, Department of Neurology, University of Miami School of Medicine, FL 33101, USA.
Stroke. 2003 Sep;34(9):2221-7. doi: 10.1161/01.STR.0000088061.06656.1E. Epub 2003 Aug 14.
A major limitation of intracerebral hemorrhage (ICH) research is the lack of reproducible animal models. The present study was conducted to validate in the mouse the double-injection method of ICH initially developed in the rat. We investigated the effect of intrastriatal injection of blood or cerebrospinal fluid (CSF) on cerebral blood flow (CBF), neurological score, hematoma volume, and brain swelling.
Male C57BL/6 mice were anesthetized with halothane/nitrous oxide delivered by face mask. Rectal and cranial temperatures were regulated at 37 degrees C to 37.5 degrees C. Mice were placed in a stereotactic frame, and a 30-gauge stainless steel cannula was introduced through a burr hole into the left striatum. Each mouse received a 5-microL injection of either whole blood or CSF (over 3 minutes), followed 7 minutes later by 10 microL injected over 5 minutes. The injection cannula was slowly withdrawn 10 minutes after the second injection. Control mice had only cannula insertion. CBF was studied by laser Doppler perfusion imaging. Neurological status was evaluated on days 1 and 2. After 2 days, hematoma volume and brain swelling were calculated.
Physiological values were stable. Mice with ICH but not those with CSF or cannula alone had a marked, persistent neurological deficit and a highly reproducible hematoma, whose mean+/-SEM volume was 2.0+/-0.2 mm3 compared with a lesion size of 0.2+/-0.1 mm3 in mice with CSF. Residual swelling of the ipsilateral hemisphere at 48 hours was 5.7% in the hematoma and 1.5% in the CSF groups. Relative CBF in the neocortex ipsilateral to the injection site declined by approximately 45% to 60% during the first 20 minutes after cannula insertion/injection in all groups but began to renormalize at approximately 25 to 30 minutes in the CSF and cannula-only groups; in the hematoma group, cortical hypoperfusion of approximately 35% to 50% persisted during the 90-minute measurement period.
The present ICH model in mice produces a consistent neurological deficit, hypoperfusion, hematoma volume, and brain swelling. This model closely mimics human hypertensive basal ganglionic ICH and should be useful for the evaluation of pharmaceutical therapies. Laser Doppler perfusion imaging is a useful new technique to quantify relative CBF changes and can be used for studies of dynamic changes of CBF in this in vivo model of ICH in mice.
脑出血（ICH）研究的一个主要局限是缺乏可重复的动物模型。本研究旨在验证最初在大鼠中建立的ICH双注射法在小鼠中的可行性。我们研究了纹状体内注射血液或脑脊液（CSF）对脑血流量（CBF）、神经功能评分、血肿体积和脑肿胀的影响。
用面罩给予氟烷/一氧化二氮麻醉雄性C57BL/6小鼠。将直肠和颅部温度调节在37℃至37.5℃。将小鼠置于立体定位框架中，通过钻孔将30号不锈钢套管插入左侧纹状体。每只小鼠接受5微升全血或CSF注射（3分钟内），7分钟后再在5分钟内注射10微升。第二次注射后10分钟缓慢拔出注射套管。对照小鼠仅进行套管插入。通过激光多普勒灌注成像研究CBF。在第1天和第2天评估神经功能状态。2天后，计算血肿体积和脑肿胀情况。
生理值稳定。脑出血小鼠而非仅注射CSF或仅插入套管的小鼠有明显的、持续的神经功能缺损和高度可重复的血肿，其平均±标准误体积为2.0±0.2立方毫米，而注射CSF的小鼠病变大小为0.2±0.1立方毫米。血肿组同侧半球在48小时时的残余肿胀为5.7%，CSF组为1.5%。在所有组中，插管/注射后的前20分钟内，注射部位同侧新皮质的相对CBF下降约45%至60%，但在CSF组和仅插入套管组中，约25至30分钟后开始恢复正常；在血肿组中，在90分钟的测量期内，皮质灌注不足约35%至50%持续存在。
目前的小鼠ICH模型产生一致的神经功能缺损、灌注不足、血肿体积和脑肿胀。该模型紧密模拟人类高血压性基底节脑出血，应有助于药物治疗的评估。激光多普勒灌注成像技术是一种有用的新技术，可量化相对CBF变化，并可用于研究该小鼠ICH体内模型中CBF的动态变化。
