Introduction Figure 1 summarizes some key aspects of the bovine estrous cycle. Changes in the 2 key structures on the ovary, the preovulatory follicle and the corpus luteum, are emphasized in this figure. The function of 4 important hormones is also summarized in this figure. Estradiol-17ß from the preovulatory follicle causes the cow to manifest estrus behaviour and have an LH surge. The LH su...

background: to achieve multiple oocytes for in vitro fertilization, ovulation induction is induced by gonadotropins however, it has several effects on oocytes and embryo quality and endometrium receptivity. the aim of this study was to assess ultrastructural changes of corpus luteum after ovarian induction using human menopausal gonadotropin (hmg) and human chorionic gonadotropin (hcg) during l...

background: congenital toxoplasmosis is one cause of abortion. infection can disrupt ovarian cycles and because toxoplasmosis is an infectious disease may have a similar effect on the ovaries. the purpose of this study was to investigate the pathological changes in the ovaries due to toxoplasmosis.   methods: tachyzoites of toxoplasma gondii were harvested from peritoneal fluid of mice, experim...

Although it is well established that the secretory activity of the corpus luteum absolutely depends on the presence of pituitary-derived luteinizing hormone (LH), it is unknown why the life span of the corpus luteum is extended during early pregnancy by the placental production of chorionic gonadotropin (CG) but regresses in the presence of LH despite the fact that CG and LH have similar action...

The rodent corpus luteum is an ephemeral structure releasing progesterone for only a few hours rather than several days. However, in response to the mating stimulus, sufficient prolactin is released from the pituitary gland in a unique pattern to activate the corpus luteum and maintain it in a secretory state for several days. Progesterone, secreted from the corpus luteum, prolongs the secretio...

Invasion of the corpus luteum by macrophages is a characteristic of luteal regression. Monocyte chemotactic protein-1 (MCP-1), a chemokine that recruits macrophages, is expressed in the rat corpus luteum where it increases in amount during luteolysis. In this study we examined the temporal and spatial expression of MCP-1 and changes in macrophage concentration in the human corpus luteum. Corpor...