ABSTRACT
Objective To establish a simple animal model of cough variant asthma(CVA)through sensitizing Brown-Norway(BN)rats with ovalbumin(OVA). Methods A total of 36 BN rats were randomly divided into three groups, including the normal control group,the model control group and the montelukast group. BN rats in the model group and the montelukast group were intraperitoneally administered with 2.0 mg of OVA and 100 mg of Al(OH)3,and the same volume of sterile saline was given to the normal group by intraperitoneal injection. Boosting was carried out by intraperitoneal administration with 0.01 mg of OVA and 100 mg of Al(OH)33 weeks later,and the rats in the normal group were injected with the same dose of physiological saline. Three weeks later,the actively sensitized BN rats were challenged with aerosolized OVA for 7 times on alternative days,and the rats in the normal group were treated with sterile saline instead of OVA. At the same time, the montelukast group was given 1.3 mg/kg of montelukast 30 minutes before atomization by intragastric administration once a day for 2 weeks,and the normal group and the model group were given the same volume of water. The tests of cough sensitivity to capsaicin and bronchial responsiveness were performed 24 h after the last administration. Results Compared with the normal group, the times of coughing(P< 0.01)and the lung resistance(RL)(P< 0.05)in the model group were significantly increased,while the lung compliance(Cdyn)was significantly decreased(P< 0.05). There was a significant difference(P < 0.05)in the times of coughing caused by capsaicin between the model group and the montelukast group. Compared with the model group,RLin the montelukast group was decreased significantly(P< 0.05), and Cdynwas increased significantly(P< 0.05). Conclusions This rat model of CVA is similar to a variety of clinical features of CVA and is easy to operate. Thus it can be used as an effective animal model of CVA.
ABSTRACT
Objective To observe the effect of intravitreal triamcinolone acetonide injection on choroidal neovascularization in brown Norway rats. Methods Thirty-six healthy brown Norway rats were divided randomly into control group (n=18) and experimental group (n=18), while one eye was chosen randomly as experimental eye. The choroidal neovascularization model was establishied, while 8μl triamcin-olone acetonide was injected in vitreous body immediately after photocoagulation in the experimental group, and the same volume isotonic balanced salt solution was injected in the control group. The eyes of six rats were enucleated for histological slices in the second, forth, and sixth week, respectively. The expression of nuclear factor-kappa B was detected with immunohistochemical method, and the max area of choroidal neovascularization was also measured. Results The area of choroidal neovascularization was smaller, and the expression of nucle-ar factor-kappa B was lower in the experimental group than in the control group (t>7.450, P<0.001). Conclusion Triamcinolone acetonide could effectively inhibit the development of choroidal neovascularization, and decrease the expression of nuclear factor-kappa B in brown Norway rats.
ABSTRACT
Background Extracellular matrix (ECM) has various kinds of types and important biological function.The important role of ECM during choroidal neovascularization (CNV) arouse attention.Intercellular adhesion molecule-1 (ICAM-1), which is one of ECMs, involves in the formation of blood vessels, but the relationship between CNV and ICAM-1 is still unknown.Objective This study was to observe the dynamic expression of ICAM-1 in krypton laser-induced CNV and explore the effect of ICAM-1 on CNV.Methods Forty-eight healthy male clean BN rats were randomly divided into post-photocoagulation 1-week group,2-week group,3-week group,4-week group, 5-week group, 6-week group, 7-week group and 8-week group.Laser-induced CNV models were monocularly established and the fellow eyes served as the normal controls.Fundus fluorescein angiography (FFA) was carried out to quantitate the leakage degree (absorbency).The eyeballs were enucleated on various time points,and CNV areas were assessed by hematoxylin and eosin staining;immunohistochemistry and in situ hybridization assay were employed, respectively, for the detection of relative expression levels of ICAM-1 protein and mRNA (absorbency).The use and care of the animals complied with the Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Committee.Results After laser photocoagulation,the retinal inner and outer nuclear layers were ruptured and invaginated.Disruption of Bruch membrane and macrophages migrating to the photocoagulation zone were seen under the optical microscope.The proliferation of fibroblasts and vascular endothelial cells was exhibited.ICAM-1 protein was mainly expressed in vascular endothelial cells,retinal pigment epithelium (RPE) cells and macrophages,and ICAM-1 mRNA was mainly expressed in the outer nuclear layer.Statistically significant differences were found in the fluorescence leakage degree, the relative expression levels of ICAM-1 protein and mRNA as well as CNV areas among the groups (F=178.839, 739.077,2 463.508,194.434, all at P＜0.05).The gradually enlarged CNV area, increased fluorescence leakage, up-regulation of ICAM-1 protein and mRNA expressions were matched with the extension of time after photocoagulation and peaked in the post-photocoagulation 8-week group.Conclusions The expressions of ICAM-1 protein and mRNA up-regulate upon the increase of CNV area and fluorescein leakage, suggesting that ICAM-1 might play an important role in CNV development.