Effects Of Azithromycin On Expression Of CHOP And GRP78 In Neonatal Rats With Hyperoxic Lung Injury

Objective:To investigate the effect of azithromycin on expression of Endoplasmic reticulum-associated factor in neonatal rats with hyperoxic lung.Methods:Select 90 female and male neonatal Wistar rats which were born 2 days and randomly divided into 3 groups included the air control (A group, n=30)、hyperoxia group(B group, n=30) and azithromycin treatment group(C group, n=30). The B group and C group were exposed in the glass cage with oxygen concentration up to 85%. The neonatal rats were admitted intraperitoneal injection of azithromycin for 14 days at the second day after birth.10 neonatal rats were sacrificed in each group at 3、7 and 14 day in order to determine W/D (wet/dry lung weight) ratio、 bronchoalveolar lavage fluid (BALF)、observe HE staining for pathological change、test the expression of Bcl-2、BaX、CHOP and GRP78 using Western blot.Results:1. Comparing with the A group, W/D ratio of 3、7 and 14 day in A group was significantly increased, and the W/D ratio of C group was decreased when compared with B group (p<0.05); 2. The number of leukocyte in BALF of B group was increased more than the A group, yet the number of leukocyte in BALF in C group was decreased more than B group; 3. Pathological observation:The lung tissue of B group had inflammatory cells exudation on 3th day, and inflammatory cells exudation become more on 7th day, then occurred fibrosis on 14th day; 4. The westernblot showed the expression of Bax in B group was higher than the A group at 3、7、14day (p<0.05), the expression of Bax of C group was decreased when compared with B group; The expression of Bcl-2 in B group was lower than the A control group, and the Bcl-2/Bax ratio in hyperoxia group was lower than the air control group, the Bcl-2/Bax ratio of B group at 3、 7、14 day was lower than the A group, and the Bcl-2/Bax ratio of C group was higher than B group (p<0.05); Comparing with the A group, the expression of CHOP and GRP78 protein in B group was significantly increased, and the CHOP and GRP78 protein expression of C group was decreased more than B group (p<0.05).Conclusion:1. Azithromycin could alleviate hyperoxia-induced inflammation and edema, regulate the expression of apoptosis factors.2. Azithromycin was protective to hyperoxia-induced lung injury and down-regulated ERS associated CHOP and GRP78 protein expression.