| Acute lung injury (ALI) is an acute progressive respiratory failure which induced by various reasons except cardiogenic factors. The serious stage of ALI is acute respiratory distress syndrome (ARDS). At present, there is still no effective therapeutic method. The mortality of ALI is 50-70%. Pulmonary alveolar macrophages (PAM) widely distributed in alveoli and in the surface of tracheal epithelial cells. They play important roles in the process of immune defence and lung injury in bronchoalveoli. During the early period of inflammation, trauma and lipopolysaccharide(LPS) can activate PAM to release various proinflammatory cytokines, one of them is tumor necrosis factor- a (TNF- a ), which lead to uncontrolled inflammatory reaction and induce ALI/ARDS. Nuclear factor- K B (NF- K B) is a protein factor that has polyphenic transcription and regulation functions. By binding to the K B sequence which exists in promoter or enhancer of the inflammatory mediums, NF- K. B can initiate and regulate the transcription of many genes, including those inflammatory factors (such as TNF,EL-l,IL-6 and IL-8). So NF- K. B has close relationship with ALI. Anisodamine was originally extracted from Anisodus Tonguticus which grows only in China. It has variety biological effects and is widely used in clinic for the treatment ofshock, microcirculatory disturbance and neuralgia. It has shown a protective effect on ALI since 80's. Recent studies showed that anisodamine could inhibit the release of cytokines such as TNF- a JL-6 and IL-8. This could reduce the inflammatory reaction. But little is known about the mechanism of anisodamine on inflammation. In this study, we observed the influence of anisodamine on the activation of NF- K B and the expression of TNF- a mRNA in RAM. The release of TNF- a and IL-8 in bronchoalveolar lavage fluid(BALF) in rabbits traumatic ALI induced by impact and LPS were detected too.Methods: Seventy-two healthy rabbits were randomly divided into three groups: (l)control group (C group), (2)injury group (I group), (3)treatment group (T group). The rabbits of I and T groups were given LPS (Onf.B4) by i.v. at a dose of 50 u g/kg after being impacted to make traumatic ALI, while the rabbits of C group were given normal saline by i.v. at the same dose. After the ALI model was made, the rabbits of T group were intravenation injected with anisodamine at a dose of 2mg/kg immediately, and then injected at Img/kg/h. The rabbits of C group were injected with normal saline instead. Every six rabbits were killed at lh,2h,3h and 4h after the model was made. BALF was collected in order to isolate RAM. The NF- K B activity of RAM and the expression of TNF- a mRNA in RAM were measured by electrophoretic mobility shift assay (EMSA) and semi-quantity reverse transcription PCR (RT-PCR). The contents of TNF- a and IL-8 in BALF were measured by enzyme linked immunosorbent assay (ELISA).Results: (1) The activity of NF- K B was obviously increased in I group compared with that of C group during l~4h (P<0.01). At 2h, the activity of NF- * B reached to the highest point (1.59 ?.07), it was 8 times as in C group. In T group, the activity of NF- K B was higher than that of in C group,but significantly lower than that of in I group (P<0.01, /><0.05). At 2h, the activity decreased from 1.59+0.07 to 1.11 ?.10. The colour of the shifted band was consistent with what mentioned above. (2) The expression of TNF-a mRNA began to increase Ih after impact and LPS stimulation, it reached to the highest point 3h after stimulation. The relative density was 1.29?.09,it was 5 times as high as the C group (P<0.01). Compared with I group, the expression of TNF- a mRNA was also obviously decreased in T group (P<0.01, /><0.05). The colour of the TNF- a cDNA PCR products band was consistent with what mentioned above. (3) In I group, the BALF contents of TNF- a and IL-8 were significantly higher than those of C group (P<0.01). They reached to the peak at 3h and 4h respectively. Their peak contents were 0.101?.008ng/ml and 1.055?.
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