[Effect of budesonide on Clara cell secretory protein and its mRNA expression in a rat model of asthma].
OBJECTIVE
To investigate the effect of inhaled glucocorticoids on the expression of Clara cell secretory protein (CCSP) and its mRNA in lung tissue of a rat model of asthma.


METHODS
The rat asthmatic model was established by sensitizing and challenging SD rats with aerosolized ovalbumin (OVA). Rats were divided into a control, an asthmatic and a glucocorticoid groups. Budesonide aerosol was delivered by a jet nebulizer. The CCSP mRNA level in the lung tissue and the CCSP level in bronchoalveolar lavage fluid (BALF) were determined by RT-PCR and dot immuno-blotting, respectively.


RESULTS
The level of CCSP mRNA in the lung tissue was 0.65 +/- 0.04 in the control, 0.56 +/- 0.05 in the asthmatic and 0.63 +/- 0.04 in the glucocorticoid groups, respectively (asthma versus control, P < 0.01; glucocorticoid versus asthma, P < 0.05). The CCSP level in BALF was 60 +/- 5 in the control, 49 +/- 5 in the asthmatic and 57 +/- 5 in the glucocorticoid groups, respectively (asthma versus control, P < 0.01; glucocorticoid versus asthma, P < 0.05). Budesonide reduced the percentage of eosinophils in BALF and inhibited airway inflammation.


CONCLUSIONS
OVA challenge in the rat model decreased CCSP mRNA, resulting in a reduction in CCSP production, which may contribute to asthmatic airway inflammation. Inhaled glucocorticoids increased the expression of CCSP mRNA in lung tissue, which may be a mechanism for the suppression of airway inflammation by glucocorticoids.
Luo
Fengming
F
Department of Respiratory Disease, Huaxi Hospital of Sichuan University, Chengdu 610041, China.
Wang
Zengli
Z
Liu
Xiaojing
X
Liu
Chuntao
C
Zhang
Xiaohong
X
Wang
Wenzhi
W
D000818:Animals; D001249:Asthma / Q000188:drug therapy* / Q000378:metabolism; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D019819:Budesonide / Q000494:pharmacology; D004195:Disease Models, Animal; D005260:Female; D008297:Male; D014176:Protein Biosynthesis; D011506:Proteins / Q000032:analysis / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014598:Uteroglobin
D011506:Proteins; D012333:RNA, Messenger; C556391:Scgb1a1 protein, rat; D019819:Budesonide; D014598:Uteroglobin