Quantitative analysis of gene expressions related to inflammation in canine spastic artery after subarachnoid hemorrhage

Abstract

Background and purpose: The possible role of inflammatory reaction of the cerebral artery in the pathogenesis of cerebral vasospasm has been noted in recent studies. We quantitatively measured the levels of expression of genes related to inflammation in the spastic artery in a canine double-hemorrhage model.

Methods: Twenty dogs were assigned to 4 groups: group D0, control; group D2, dogs killed 2 days after cisternal injection of blood; group D7, dogs given double cisternal injections of blood and killed 7 days after the first injection; and group D14. Angiography was performed twice: on the first day and before the animals were killed. Total RNA was extracted from the basilar artery. The expressions of interleukin (IL)-1alpha, IL-6, IL-8, IL-10, tumor necrosis factor-alpha, E-secretin, fibronectin, intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule-1, transforming growth factor-ss, basic fibroblast growth factor, and collagen types I, III, and IV were examined with TaqMan real-time quantitative reverse transcription-polymerase chain reaction.

Results: Prolonged arterial narrowing peaking on 7 day was observed. There was a significant difference in vessel caliber between D0, D2, D7, and D14 groups (P:<0.0001). There were significant differences in mRNA expression in the basilar artery for IL-1alpha, IL-6, IL-8, ICAM-1, and collagen type I between D0, D2, D7, and D14 groups (P:=0.0079, 0. 0196, 0.0040, 0.0017, and <0.0001, respectively). The average level of mRNA was highest in D7 for IL-1alpha, IL-6, IL-8, and ICAM-1 (17-, 16-, 131-, and 1.7-fold compared with those of D0, respectively) and in D14 for collagen type I (10.9-fold).

Conclusions: Increased expression of genes related to inflammation in the spastic artery suggests that inflammatory reaction of the cerebral artery is associated with sustained contraction.