Formation and Maintenance of Corpora Lutea in Domestic Animals

THE corpus luteum is an endocrine gland which plays an active, yet transitory role in female mammals after puberty. During every luteal phase, the length of which varies with the species, hormones influence the formation, growth, secretory activity, and degeneration of the gland. Some hormones cause cellular differentiation and multiplication, phenomena which lead us to think that these substances affect nucleic acids. In a brief interval of a few days events occur, which, in other organs may be spread out over a lifetime. This fact draws our attention to the complexity of the rather short-term hormonal regulation which influences luteal cells.Research done during the last 10 yr., mostly on domestic animals, indicates that there are two hormonal systems affecting the corpus luteum. The first ensures morphogenesis and induces or stimulates progesterone secretion, whereas the second causes rapid stoppage of secretory phenomena and morphological regression. Luteolytic effects, principally, but not exclusively, of the uterus, have been the subject of a report by Dr. Melampy and will not be discussed here.