Glycoprotein hormones, hCG and eCG, are synthesized in women and mares...
Glycoprotein hormones hCG and eCG
Introduction
Glycoprotein hormones, such as human chorionic gonadotropin (hCG) and equine chorionic gonadotropin (eCG), play crucial roles during pregnancy in women and mares, respectively. These hormones are synthesized by the placenta and exhibit specific activities in their respective species.
Characteristics of hCG and eCG
Both hCG and eCG are glycoprotein hormones that share structural similarities and belong to the same family of hormones. However, they have distinct physiological functions and activities.
Activity of hCG in Women
In women, hCG has LH (luteinizing hormone)-like activity. LH is responsible for the final stages of follicular maturation, ovulation, and luteinization in the menstrual cycle. During pregnancy, hCG is produced by the placenta and maintains the corpus luteum, which produces progesterone to support the pregnancy. This LH-like activity of hCG is crucial for the maintenance of pregnancy and the development of the fetus.
Activity of eCG in Mares
In mares, eCG has primarily FSH (follicle-stimulating hormone)-like activity. FSH stimulates the development and growth of ovarian follicles in the mare's reproductive system. During pregnancy, eCG is produced by the endometrial cups, which develop on the surface of the placenta in mares. The FSH-like activity of eCG promotes follicular development and maturation, leading to the production of estrogen and the formation of secondary corpora lutea.
Activity of hCG and eCG in Other Species
While hCG and eCG have specific activities in women and mares, respectively, they do not have the same activity in other species. In other species, including non-pregnant women and mares, these hormones may have limited or no biological activity. Therefore, they are considered species-specific hormones.
Applications in Women
In women, hCG is routinely employed in assisted reproductive technologies (ART) to promote final stages of follicular maturation, induce ovulation, and support pregnancy. It is also used in the treatment of infertility, as it mimics the action of LH and can stimulate the release of mature eggs from the ovaries.
Conclusion
Glycoprotein hormones, hCG and eCG, have distinct activities in women and mares, respectively, during pregnancy. While hCG exhibits LH-like activity in women, eCG primarily acts as an FSH-like hormone in mares. These hormones play essential roles in the reproductive processes of their respective species and have clinical applications in the field of reproductive medicine.