Water-Soluble Glycoprotein Ovarian Hormone

Which of the following ovarian hormones is glycoprotein in nature and soluble in water?

Correct Answer: Relaxin

Relaxin is the only ovarian hormone that is a glycoprotein in nature and is therefore water-soluble. It belongs to the insulin-like peptide family.

Chemical Nature of Ovarian Hormones

• Estrogen (Estradiol): Steroid hormone — lipid-soluble, derived from cholesterol
• Progesterone: Steroid hormone — lipid-soluble, derived from cholesterol
• Androgen (Testosterone): Steroid hormone — lipid-soluble
• Relaxin: Glycoprotein (peptide) — water-soluble ✔

Function of Relaxin

• Softening and relaxation of pelvic ligaments and the pubic symphysis in preparation for parturition
• Relaxation of the cervix for dilation during labour
• Inhibition of uterine contractions during pregnancy
• In females, secreted by the corpus luteum (especially in dogs and pigs), placenta, and uterus