Apoptosis induced by droloxifene and C-myc, Bax, Bcl-2 protein expression in corpus luteum of pregnant rats.
OBJECTIVE
To investigate the effects of droloxifene on apoptosis of luteal cells in pregnant rats, and analyze the possible relationships between the expression of C-myc, Bax, Bcl-2 protein in corpus luteum and apoptosis of luteal cells induced by droloxifene.


METHODS
Pregnant rats were treated orally with droloxifene 20 mg . kg-1 on d 2. Ovaries were collected on d 4 or d 8 for detecting the apoptosis of luteal cells by hematoxylin-eosin staining and terminal deoxyribonucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labelling (TUNEL), and observing the expression of C-myc, Bax, Bcl-2 protein in corpus luteum by immunohistochemistry. The ovarian fresh weight, protein contents, and serum progesterone levels were also determined on d 4 and d 8.


RESULTS
Apoptotic luteal cells appeared on d 4 and more apoptotic cells could be observed on d 8 in droloxifene treated rats. The ovarian fresh weight, protein contents, and serum progesterone concentration were found to be decreased significantly on d 8 as compared to the control group. In corpus luteum of droloxifene treated rats, the increased expression of C-myc and Bax protein could be observed on d 4 and d 8, respectively, whereas no obvious changes could be found in the expression of Bcl-2 protein.


CONCLUSIONS
Droloxifene could induce apoptosis of luteal cells of preimplantation in pregnant rats. An increased expression of C-myc protein and Bax/Bcl-2 ratio could be induced by droloxifene, which might be associated with the mechanisms of apoptosis of luteal cells induced by droloxifene.
Leng
Y
Y
Shanghai Institute of Material Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China. zpgu99@yahoo.com
Gu
Z P
ZP
Cao
L
L
D000818:Animals; D017209:Apoptosis; D004965:Estrogen Antagonists / Q000494:pharmacology; D005260:Female; D008184:Luteal Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D011247:Pregnancy; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013629:Tamoxifen / Q000031:analogs & derivatives* / Q000494:pharmacology*; D051028:bcl-2-Associated X Protein
C494828:Bax protein, rat; D004965:Estrogen Antagonists; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016271:Proto-Oncogene Proteins c-myc; D051028:bcl-2-Associated X Protein; D013629:Tamoxifen; C038345:droloxifene