Objective To observe the effects of ambroxol injection on mucosal surface structure of trachea injured by intratracheal instillation of amikacin. Methods 280 Wistar rats were randomly divided into four groups( n = 70 in each group) , ie. a normal control group, a normal saline group( intratracheally instilled normal saline) , an amikacin group ( intratracheally instilled amikacin) , and an ambroxol group ( intratracheally instilled amikacin and ambroxol simultaneously) . At the time points of 2, 12, 24, 48, 72 hours six animals in each group were killed and the samples of 1/3 lower segment of trachea were collected and observed by scanning electron microscope. Endotracheal intubation were made on other 6 animals to collecte broncho-alveolar lavage fluid ( BALF) for leucocyte count. Results Compared with the normal control group, elevated leucocyte count was observed in all other groups, various grades of swelling of the cilia were revealed, followed by more or less cilia laid flat with adjacent cilia conglutinated. Then partial cell membrane on top of some cilia bulged out. In terms of injury, the normal saline group was the most mild, and the amikacin group was most serious with the highest leucocyte count. All the parameters were relieved in ambroxol group. Conclusions Intratracheal instillation of amikacin causes acute injury of the ultrastructure of mucosal surface cilia. Ambroxol can promote the recovery process and alleviate inflammation of airway.
Objective To investigate the effects of ambroxol hydrochloride on surface structure of trachea mucosa in rats injured by intratracheally instilled amikacin. Methods Thirty Wistar rats injured by intratracheally instilled amikacin ( 0. 252 mL/kg) were randomly divided into a control group ( n =15) and an ambroxol group ( n= 15) . The rats in the ambroxol group were intraperitoneally injected with ambroxol hydrochloride ( 70 mg/kg) 5 minutes after amikacin administration. They were all equally divided into five subgroups and sacrificed at 2, 4, 8, 28, 48 hours respectively. Then the samples of 1/3 lower segment of trachea were collected and observed under scanning electron microscope. Results In the control group, the mucous secretion and its stickness were increased. The cilia were found lodged, sticked together, aligned abnormally, abrupt partly, and recovered slowly, with the percentage of damaged area of 98. 2% , 98. 5% , 97. 5%, 92. 7% , 82. 1% at 2, 4, 8,24,48 h, respectively. The injuries of mucosa in the ambroxol group were much milder and recovered more rapidly than those in the control group, with the percentage of damaged area of 85. 7% , 81. 9% , 73. 0% , 61. 9% , 50. 2% at 2, 4, 8, 24, 48 h, respectively. Conclusions Intratracheal instillation of amikacin can cause cilia ultrastructure damage on tracheal mucosa. Ambroxol can promote the recovery process and alleviate airway inflammation.