Two models of cerebral vasospasm after subarachnoid hemorrhage in rats

Abstract

Objective To establish and compare the early cerebral vasospasm (CVS) caused by 2 subarachnoid hemorrhage (SAH) models. Methods Thirty⁃nine Wistar rats were divided into 3 groups: control group, single injection group and double injection group. Rat subarachnoid hemorrhage was induced by single or double injection of autologous blood into the cisterna magna. A second injection was given after 48 h in double injection group. Perfusion ⁃ fixation was performed after 24 h of receiving the last intracisternal injection of blood, and then brain tissue and basilar artery were removed. HE staining was used to examine morphology and cross ⁃sectional areas of the basilar artery. The ultrastructural changes were observed by electron microscope. Results There were obvious clots in the basilar region, and decreasing cross⁃sectional areas in the 2 kinds of injection groups (F = 5.460, P = 0.012). Cross⁃sectional areas of basilar artery in single injection group were slightly decreased [(2.68 ± 0.48) × 10 ⁃ 2 mm2], and the difference compared with control group was not significant (q = 2.630, P = 0.070). Cross⁃sectional areas of basilar artery in double injection group were significantly decreased compared with control group [(2.41 ± 0.24) × 10 ⁃ 2 mm2; q = 4.660, P = 0.003], but there was no significant difference with single injection group (q = 2.031, P = 0.166). Ultrastructural changes of the artery wall and hippocampus were observed in injection groups, including dystrophy of endotheliocyte, vacuolated cytoplasm, distortion of smooth muscle cell and corrugation of intimal elastic lamina. Conclusion Blood injection into the cisterna magna in rats can establish early cerebral vasospasm model after subarachnoid hemorrhage. The double injection group is more stable. DOI：10.3969/j.issn.1672-6731.2010.04.016

Keywords

• Subarachnoid hemorrhage
• Vasospasm, intracranial
• Microscopy, electron, transmission
• Disease models, animal