Compensatory ovarian changes, mast cell distribution and luminal structure changes following unilateral ovariectomy in rats

Document Type : Full paper (Original article)


1 Department of Basic Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran

2 Department of Basic Sciences, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran


To follow-up the present study, 40 mature female rats were used. The animals were divided into test,
control and sham groups. The rats in the test group were laparotomized and unilateral ovariectomy was done. On the 1st and 2nd met-oestrous after operation, the tissue samples were dissected out and processed for histological study. The intact ovary in the test group underwent a significant (P<0.05) hypertrophy and compensatory changes including double angiogenesis, high cytoplasmic vacuolation in granulosa cell types of corpus luteum, compensatory follicular development, decreasing of follicular atresia, approximately double ovulation rate and increase in the width of cortex and medulla. The uterine horn on the intact side was approximately similar to the control and sham, while morphometric analyses showed that the horn on the ovariectomized side had significant decrease in the thickness of different layers. Scattering of endometrial glands on the uterine horn of the intact side was normal, showing a dense basophilic appearance in haematoxyline and eosin staining sections. The horn on the ovariectomized side showed low gland scattering. Histomorphometric analyses showed no significant differences between the vaginas in the three different groups. Distribution of mast cells (MCs) as essential cells participating in angiogenesis was investigated. In the test group, mast cells were considerably increased in number around the blood vessels in the medulla of the intact ovary and intact uterine horn. Mast cells were very low in number on the horn on the ovariectomized side.