Corpus luteum growth and endocrine function are closely dependent on the formation of new capillaries. The objectives of this study were to evaluate (i) tissue growth and microvascular development in the equine cyclic luteal structures; (ii) in vitro angiogenic activity of luteal tissues in response to luteotrophic (LH, PGE(2)) and luteolytic (PGF(2alpha)) hormones and (iii) to relate data to l...

Gonadotrophin-releasing hormone agonists (GnRHa) are widely used in in-vitro fertilization (IVF) for the prevention of a premature rise in luteinizing hormone (LH) concentrations. However, the administration of GnRHa during the follicular phase may also impair subsequent luteal function due to retarded recovery of pituitary gonadotrophin secretion. Therefore, luteal supplementation is generally...

Ephemerality and prolongation of luteal function have been matters of great concern in reproduction for many years. However, their control mechanisms are very complex and differ among mammals. Recently, evidence has indicated that reactive oxygen species may play important roles in the regulation of luteal function. Reactive oxygen species are present in most somatic cells and are involved in a...

Forty six Holstein Friesian repeat breeding cows (the average AI/conception was 5.2 ± 0.2) were investigated using the progesterone assay after AI to determine possible differences in plasma progesterone profiles between summer and winter seasons. Twenty eight (60.9%) and 18 (39.1%) cows were followed in summer (June–August) and winter (December–February), respectively. In the summer season, th...

The first report of the combined use of pituitary suppression and ovarian hyperstimulation in invitro fertilization (IVF) and embryo transfer programmes was published in 1984 (1). Since then, the advantages of gonadotrophin hormonereleasing hormone analogues (GnRHa) have been well documented; the cancellation rate has been decreased through the prevention of premature luteinizing hormone (LH) s...

Luteinizing hormone (LH) regulates several ovarian functions. However, the luteoprotective mechanisms of LH involved in the maintenance of bovine corpus luteum (CL) function are not well understood. Since prostaglandin F2α (PGF), PGE2 and progesterone (P4) are well documented as antiapoptotic factors in the bovine CL, we hypothesized that LH protects the CL by stimulating the local production a...

Human luteal cells have been reported to express human leukocyte antigen-DR and lymphocyte functional antigen-3 on the cell surface, suggesting physiological interaction between luteal cells and T-lymphocytes through the menstrual cycle into early pregnancy. To elucidate the role of peripheral lymphocytes on corpus luteum differentiation, the effect of peripheral blood mononuclear cells (PBMC) ...