Protective effects of laminarin on vascular endothelium in rats with chronic inflammation induced by LPS / 中国药理学通报

ABSTRACT

Aim To observe the effect of laminarin L01 on the expression of eNOS and iNOS in aorta of rats with chronic inflammation induced by LPS. Methods Chronic inflammatory rat models were prepared by tail vein injection low dose LPS(0.4 mg·kg-1) once a week for four weeks. The rats were randomly divided into five groups. After the first injection of LPS, the DXM group was intraperitoneally injected with dexam-ethasone (10 mg·kg-1). L01 high,medium and low dose groups were intraperitoneally injected with L01 (50,30,10 mg·kg-1). The LPS group was injected intraperitoneally with equal volume of normal saline once a day. Another control group, only injection of normal saline, a total of four weeks. After the last administration,the number of whole white blood cells (WBC) was counted. ELISA was used to measure the hs-CRP in serum. The expressions of eNOS,iNOS and COX-2 mRNA were detected by RT-PCR. Results After four weeks of administration of L01, the number of WBC and the level of serum hs-CRP in chronic in-flammatory rats were significantly decreased. The ex-pression of eNOS was up-regulated, and iNOS and COX-2 expressions were down-regulated. Conclusions Laminarin L01 may regulate the expression and re-lease of endothelium-derived relaxing factor stimulated by LPS,and improve the endothelium-dependent dias-tolic function of aorta, thus protecting the damage of vascular endothelium.