Effect of aspirin on the expressions of intercellular adhesion molecule 1 and calcitonin-gene-related peptide in gerbils with ischemic reperfusion injury

Shuang LIU; Yizhao LI; Tao ZHANG

ABSTRACT

BACKGROUND:

With the development of thrombolysis therapy in recent years, there has been an increasing focus on the protective effect of ischemic reperfusion injury (IRI) and its mechanism at home and abroad,and aspirin is of great importance in the treatment of thrombus diseases owing to its powerful antiplatelet aggregative activity.

OBJECTIVE:

To explore the protective effect of aspirin on the gerbil brains with IRI and its influence on the intercellular adhesion molecule (ICAM) and calcitonin gene-related peptide (CGRP) expressions.

DESIGN:

A randomized controlled animal experiments.

SETTING:

Department of Neurology, Jinan Municipal Central Hospital,College of Clinical Medicine, Shandong University.MATERIALS The experiment was performed at the Physiological Laboratory of Taishan Medical University from December 2001 to June 2002.Sixty-three healthy male gerbils of Mongolian specimen were randomly assigned into sham group, IRI group and aspirin group with 21 in each group. And each group was further divided into three subgroups according to the time after IRI 24 hours, 3 days and 7 days, with 7 gerbils for each.

METHODS:

The models of global brain IRI were established by bilateral carotid artery occlusion. Sham group The unfolded bilateral carotid artery was not occluded; IRI group The unfolded bilateral carotid artery was occluded by bulldog clamp for 7 minutes, and then the blood circulation was recovered by removing the clamp. Aspirin group Before the operation,50 mg/kg enteric-coated aspirin was infused via gastric canal. And the same procedures as IRI group were performed. The gastric infusion of aspirin was given daily until the gerbils were executed at 24 hours, 3 days and 7 days after IRI for brain tissue examinations. The immunohistochemistry SABC method was applied to detect the changes of ICAM 1 and CGRP expressions as well as the influence of aspirin on the two.MAIN OUTCOME

MEASURES:

The expressions of ICAM and CGRP in brain tissues.

RESULTS:

A total of 63 gerbils were involved in the result analysis.①Changes of ICAM expression In IRI group, the expression of ICAM began to increase at 24 hours after IRI,enhanced remarkably at 3 days and maintained at high levels at 7 days,with the significant difference compared with sham group [IRI group (3.36±2.26)%, (5.68±3.13)%, (4.98±2.10)%; Sham group (1.53±1.07)%, (1.56±1.23)%, (1.62±1.33)%, P ＜ 0.05];However,the ICAM expression was significantly lower in aspirin group than in IRI group at different time points [(0.96±0.83)%, (2.76±2.10)%,(1.96±1.09)%, P ＜ 0.05].②Changes of CGRP expression At the different time points after IRI,the CGRP expression was weakly positive in IRI group [(3.12±2.26)%, (2.68±2.04)%, (2.57±1.97)%], but strongly positive in aspirin group [(4.98±2.47)%, (5.97±2.35)%, (6.04±2.40)%].

CONCLUSION:

IRI can increase the ICAM 1 expression while inhibit the CGRP expression; Aspirin can make great impacts on brain protection by inhibiting ICAM 1 expression and reinforcing the CGRP expression.