Influence Mechanism Of L-Arg On The Proliferation Of Airway Smooth Muscle Cell With Rat Asthma Model

Objective: To investigate the influence of L-Arginine (L-Arg) on the cell cycle distribution and the expression of cell cycle regulatory proteins in the proliferation of airway smooth muscle cell (ASMC) with rat asthma model.Methods: 60 rats were randomly divided into three groups including control group, asthmatic group, therapeutic group. In the experiment, the rat asthma model was established by sensitizing with injection of ovablumin together with AL(0H)₃, then challenged by repeatedly exposing to aerosolized ovalbumin. The levels of serum nitric oxide (NO) were measured by nitrate reductase; Rats pathologic changes of airway wall with the hematoxylin staining were observed by the optic microscope, the thickness of inner airway wall and smooth muscle layer were measured by image analysis system; The cell cycle distribution of ASMC was analyzed by flow cytometry; Immunohistochemisty was employed to observe the expression of cell cycle regulatory proteins(CCRP) cyclin E, cyclin A, cyclin B and P27^kiplin ASMC.Results: (l)The thickness of inner airway wall, smooth muscle layer and the number of ASMC nucleus in rats of asthmatic group were much morer than those in control group; The thickness of inner airway wall, smooth muscle layer and the number of ASMC nucleus in rats of therapeutic group were much smaller than those in asthmatic group and were higher than those in therapeutic group. (2)The levels of serum NO were obviously lower in rats of asthmatic group than those in therapeutic group, however the levels of serum NO were significantly higher in rats of therapeutic group than those in control group. (3)The percentage of ASMC in the G₀/Gi phase in asthmatic group was significantly lower than that in control group. Whereas , the percentage of ASMC in the S phase...