Objective: To investigate the changes of cell proliferation state after denervation of laryngeal adducent muscles in dog.
Methods: The muscles were obtained from 8 dogs with recurrent lanyrgeal nerves injured. The cross sectional areas of muscle cells were measured by VIDS Image Analysis System in HE stained sections. A quantitative collagen/muscle ratio was measured by TJTY-300 image analysis system in Van Gieson stained sections. The percentages of S phase cell nucleus were calculated by image cytometry/DNA quantitative analysis with CAS 200 System.
Results: It showed that the cross sectional area of muscle cells decreased gradually after denervation (out-standing in 6 months after denervation) and collagen/muscle ratio increased significantly with time. The percentage of S phase nucleus was high at 5 months and then decreased.
Conclusion: The proliferation of thyroarytenoid muscle and lateral cricoarytenoid muscle cell of dog remained at high level in 5 months after denervation and then slowed down and atrophy of muscles occurred 6 months after denervation. This suggests that nerve repair should be performed early. Examination of cell proliferation might indicate if the denervation of cells irreversible. It is helpful in choosing proper surgery and estimating the effect of nerve repair.