The effect of tibolone on endometrial IGF-1 and IGFBP-1 levels in ovariectomized rats.
OBJECTIVE
The goal of this study was to search the effects of two different doses of tibolone on endometrial IGF-1 and IGFBP-1 levels in ovariectomized rats.


METHODS
Eighteen adult, female, 80-90-days-old, Wistar rats with an average weight of 250 g underwent bilateral ovariectomy under general anesthesia. After waiting for 4 weeks, they were randomized into three groups to receive either oral tibolone in two different doses or placebo. The treatment was continued for 5 weeks, and then the rats were sacrificed and the endometria were analyzed.


RESULTS
Low columnar epithelium of the endometrial surface, longer epithelium and stratified squamous epithelium were seen in the control, low-dose and high-dose groups, respectively. The staining intensity of IGF-1 was mild in control, and moderate in both treatment groups, the difference between control the treatment groups was significant (P=0.015 for group L, and P=0.03 for group H). The staining intensity of IGFBP-1 was moderate in control, and strong in groups L and H. Again the difference was significant between control and both treatment groups (P=0.039 for grup L, and P=0.03 for group H). No significant difference was noted between each treatment group for both IGF-1 and IGFBP-1.


CONCLUSIONS
Tibolone caused histological changes in endometrium and stimulated IGF-1 and IGFBP-1 staining. Both low and high dose treatments led to moderate and strong staining intensities for IGF-1 and IGFBP-1, respectively. The strong staining intensity of IGFBP-1 is likely due to the progestagenic effect of tibolone.
Kuşcu
N Kemal
NK
Department of Obstetrics and Gynecology, School of Medicine, Celal Bayar University, 45020 Manisa, Turkey. nkk@ixir.com
Koyuncu
Faik M
FM
Inan
Sevinc
S
Tuglu
Ibrahim
I
Uyar
Yildiz
Y
Ozbilgin
Kemal
K
D000818:Animals; D004717:Endometrium / Q000378:metabolism / Q000473:pathology*; D020847:Estrogen Receptor Modulators / Q000494:pharmacology*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D009652:Norpregnenes / Q000494:pharmacology*; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar
D020847:Estrogen Receptor Modulators; D018970:Insulin-Like Growth Factor Binding Protein 1; D009652:Norpregnenes; D007334:Insulin-Like Growth Factor I; C027385:tibolone