Regulation of Relaxin Secretion and its Role in Pregnancy

  • L. L. Anderson
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 219)


Relaxin plays a critical role in suppressing uterine motility during pregnancy and in remodeling connective tissue in preparation for imminent parturition. Its biological actions in softening the cervix and symphysis pubis in the guinea pig were first described by Hisaw (1926). Numerous biological studies were conducted with partially purified preparations of relaxin which led to a consensus of its importance in reproductive processes. Following the purification and characterization of porcine relaxin by Sherwood and O’Byrne (1974), there has been intensive research on the chemistry of relaxin and its physiology. Although relaxin is produced primarily during pregnancy in several mammalian species, it also is found in the male reproductive tract and can maintain sperm motility but little is known of its physiological significance (Loumaye et al., 1980; Essig et al., 1982). Recent reviews on relaxin include those by Bryant-Greenwood (1982; 1985), Porter (1984) and Kemp and Niall (1984). This review will briefly describe the current status of the species sources of relaxin, cellular localization of the hormone, and the biological actions of relaxin particularly during pregnancy. Major emphasis will be placed on the regulation of relaxin secretion during pregnancy in the rat and farm animals.


Luteinizing Hormone Corpus Luteum Estrous Cycle Late Pregnancy Luteal Cell 
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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • L. L. Anderson
    • 1
  1. 1.Department of Animal ScienceIowa State UniversityAmesUSA

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