Sun A, Zhu P, Wang J, Ge Q
Department of Gynecology and Obstetrics, PUMC Hospital, CAMS and PUMC, Beijing 100730, China.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2000 Dec;22(6):573-6.
To investigate the mitotic index (MI) and proliferating cell nuclear antigen (PCNA) index in monitoring the rat endometrium during estrogen and progestin administration.
One hundred and sixty Sprague-Dolly rats were randomly divided into seven groups. The 1st and 2nd group were normal estrous (E) and ovariectomized (OVX) control. The other groups received estradiol (E2V) only or combined with medroxyprogesterone(MPA) which imitated the clinical regimen in different dosage and different time before sacrificed. Uteri sections were stained with HE and immunohistochemical procedures to detect mitosis and PCNA.
The MI and PCNA index were similar in the luminal and glandular cells. Both markers were low in the two control groups and increased with the E2V dosage in the treatment group. But if E2V was given for 1 to 21 days, the MI increased during the first 3 days and then dropped to low level and kept to the end. PCNA index increased in the first 3 days and decreased to a low level on the 4th day and then increased gradually to a high level until the last day. In the continuous regimen, both markers decreased as the MPA dosage increased. In the cyclic regimen, The MI reached to a significant low level nearly to zero in almost each ratio. Addition of MPA for 10 days, PCNA index at the ratio of 1:4.0 could be reduced to a low level and addition for 5 days, PCNA index in each subgroup was still as high as the positive control even though the dosage of MPA increased several times to 1:8.0.
This study suggests that PCNA index can reflect both the effect of estrogen and progestogen. PCNA index is better than mitotic index in reflecting the change of endometrium.
