BAPTA-AM is a standard tool agent of calcium chelating.After entering into cells,BAPTA-AM is metabolized by lipase and forms BAPTA.The latter combines with calcium ion rapidly and high selectivity.The effects of BAPTA-AM can effectively protect nerve cells against hypoxic/ischemic injury and protect hepatocytes against cytotoxins attack.BAPTA-AM is a hopeful candidate for treating stroke,liver failure and other clinical critical diseases.

OBJECTIVE To investigate the improvement effect and mechanism of desloratadine citrate disodium in mice with hypersensitivity pneumonitis （HP）. METHODS Sixty mice were randomly divided into blank control group （normal saline）， model group （normal saline）， prednisone group （positive control， 20 mg/kg） and desloratadine citrate disodium low-， medium- and high-dose groups （0.5， 1， 2 mg/kg）， with 10 mice in each group. Except for the blank control group， mice in other groups were intraperitoneally injected with ovalbumin （OVA） and exposed to OVA inhalation to establish the HP model. On day 22 post- modeling， mice in each group were administered the corresponding drugs or normal saline， once a day， for 11 consecutive days. After the last administration， lung function and airway hyperreactivity were assessed. The levels of interleukin-1β （IL-1β）， IL-4 and IL-6 in serum as well as the levels of IL-8， IL-13 and IL-17A in bronchoalveolar lavage fluid were determined. Pathological changes in lung tissue of mice were evaluated using Masson staining. Furthermore， the expressions of fibrosis-related proteins， including transforming growth factor β1 （TGF-β1）， type Ⅲ collagen （Col-Ⅲ） and fibronectin （FN） were determined in lung tissues. RESULTS Compared with the blank control group， the model group showed significant deterioration in lung function （P＜ 0.01）， while airway resistance and serum levels of IL-1β， IL-4， IL-6 and the levels of IL-8， IL-13 and IL-17A in the bronchoalveolar lavage fluid were increased significantly （P＜0.01）. The lung tissues exhibited alveolar collapse， atrophy， and structural disarray， along with the formation of extensive deposits of blue collagen fibers， the percentage of positive staining increased significantly （P＜0.01）. Additionally， the expression levels of TGF-β1， Col-Ⅲ， and FN proteins in the lung tissues were also increased significantly （P＜0.01）. After intervention with desloratadine citrate disodium， the pathological changes in the lung tissues of mice in each dosage group of desloratadine citrate disodium showed varying degrees of improvement， and most of the aforementioned indicator levels were significantly reversed （P＜0.05 or P＜0.01）. CONCLUSIONS Desloratadine citrate disodium can improve the lung function and airway hyperreactivity of HP mice， inhibit the release of inflammatory factors in serum and bronchoalveolar lavage fluid， and reduce the deposition of collagen fibers. Its mechanism of action may be related to anti-inflammatory， immunomodulatory， and antifibrotic effects.