Immunosuppressed rat model of cerebral hemorrhage:construction and assessment / 中国组织工程研究

ABSTRACT

BACKGROUND:Treatment after intracerebral hemorrhage can effectively suppress immune function. The immune suppression after ischemic stroke has been studied in detail. OBJECTIVE:To construct an immunosuppressed rat model after cerebral hemorrhage, and assess its stability. METHODS:Sixty Wistar rats were randomly divided into control group, sham group, and cerebral hemorrhage group, with 20 rats in each group. Rat models of acute cerebral hemorrhage were established by 50μL arterial blood injection in the rat basal ganglia. Rats in the sham group were injected with 50μL of saline, and the operation was identical to cerebral hemorrhage model. Rats in the control group received no treatment. At 24, 48, 72 and 96 hours after model establishment, leukocytes, lymphocytes, and lymphocyte percentage were analyzed by blood analyzer. Enzyme linked immunosorbent assay was used to determine the levels of serum proinflammatory cytokine interleukin-6 and anti-inflammatory cytokine transforming growth factorβin rats. Dissected rat spleen tissue was subjected to histological and histopathological detection. RT-PCR and western blotting were utilized to measure changes in transforming growth factorβ, interleukin-6 gene and protein expression in the spleen. RESULTS AND CONCLUSION:(1) Compared with the sham group and control group, leukocyte number was significantly higher, but lymphocyte percentage gradual y reduced in the cerebral hemorrhage group at 24, 48, 72 and 96 hours (P<0.05). (2) Compared with the sham group and control group, interleukin-6 levels in the blood and spleen were higher at 24 hours, peaked at 72 hours, and decreased at 96 hours in the cerebral hemorrhage group (P<0.05). (3) Compared with the sham group and control group, transforming growth factorβexpression was lower at 24 hours, gradual y increased at 72 hours, and higher at 96 hours in the rat blood and spleen of the cerebral hemorrhage group (P<0.05). (4) These findings indicate that immune function excitement first appeared after cerebral hemorrhage, and immune suppression appeared at 96 hours, indicating successful model establishment and good stability.