From Simple English Wikipedia, the free encyclopedia
Relaxin molecule

Relaxin is a peptide hormone.[1]

Function[change | change source]

In humans[change | change source]

Relaxin is produced in females. It rises to a peak about 14 days after ovulation, and then declines if the egg is not fertilised. During the first three months of pregnancy, levels rise and more relaxin is produced. Relaxin adjusts blood supply during pregnancy. It also relaxes pelvic ligaments.[2] It softens the pubic symphysis (the ligaments joining the bottom of the pelvis).

In males, relaxin also has a function: it enhances motility of sperm in semen.[3]

In other animals[change | change source]

In animals, relaxin widens the pubic bone and facilitates labor. It also softens the cervix (cervical ripening), and relaxes the uterine musculature. Thus, for a long time, relaxin was looked at as a pregnancy hormone. However, its significance may reach much further. Relaxin affects collagen metabolism, inhibiting collagen synthesis and enhancing its breakdown.[4]

References[change | change source]

  1. Bani D (1997). "Relaxin: a pleiotropic hormone". General Pharmacology. 28 (1): 13–22. doi:10.1016/s0306-3623(96)00171-1. PMID 9112071.
  2. Conrad K.P. (2011). "Maternal vasodilation in pregnancy: the emerging role of relaxin". Am. J. Physiol. Regul. Integr. Comp. Physiol. 301 (2): R267–75. doi:10.1152/ajpregu.00156.2011. PMC 3154715. PMID 21613576.
  3. Weiss G (1989). "Relaxin in the male". Biol. Reprod. 40 (2): 197–200. doi:10.1095/biolreprod40.2.197. PMID 2497805. Archived from the original on 2008-11-22. Retrieved 2017-06-24.
  4. Tang, Mimi L. K.; Samuel, Chrishan S.; Tregear, Geoffrey W.; Royce, Simon G.; Solly, Natasha R.; Mookerjee, Ishanee (2006). "Endogenous relaxin regulates collagen deposition in an animal model of allergic airway disease". Endocrinology. 147 (2): 754–61. doi:10.1210/en.2005-1006. PMID 16254028.