OBJECTIVEThis research aims to further explore the expression and significance of proliferating cell nuclear antigen (PCNA) and P53 in regenerating rat atrophy parotid gland from the gene and protein levels.

METHODSOne hundred and two Wistar rats were randomly divided into experimental and control groups; the former group's duct was ligated and then released respectively in 7 (Group A) and 14 days (Group B). Fresh parotid specimens were obtained at 0, 3, 5, 7, 10, 14, 21, and 28 days after being released. Hematoxylin-eosin staining method was used to observe the morphological changes of the parotid gland. The significance of P53 and PCNA in two groups was resolved by real-time fluorescence quantitative polymerase china reaction and Western blot.

RESULTSAcinar cells aoptosis and duct cells proliferation occurred when the occlusion of the parotid duct was reversed on days 7 and 14. The expression of P53 was higher than that of PCNA, and they reached the peak at the third and fifth days after groups A and B regenerated, respectively. This finding was significantly different compared with the control (P<0.01). P53 and PCNA contents decreased gradually; acinar and duct gradually returned to normal morphology; PCNA and P53 contents gradually close to the normal control group.

CONCLUSIONSAfter ligating the parotid duct, P53 was highly expressed, and induced parotid gland atrophy. Mean-while, PCNA was highly expressed, which then decreased inducing gland recovery.