title: No effects of human relaxin on the active and passive biomechanical properties of isolated cervical specimens from nonpregnant women.
abstract: OBJECTIVE
  To evaluate the effect of human relaxin (hRLX-2) on the active and passive biomechanical properties of cervical tissue in vitro.
  
  
  METHODS
  Cervical samples were obtained from the middle part of the cervix in 22 nonpregnant women undergoing hysterectomy.
  
  
  METHODS
  The effect of hRLX-2 (10(-7) M) on the active biomechanical properties was studied on vasopressin (10(-8) M) induced smooth muscle contractions in an organ bath model. The effect on the passive biomechanical properties were studied after incubation of the strips for 48 h with hRLX-2 (10(-8) M and 10(-9) M). Subsequently, the specimens were stretched in a material testing machine until they broke. The load applied and the elongation were simultaneously recorded and the results translated into stress-strain curves.
  
  
  RESULTS
  hRLX-2 did not influence the vasopressin-induced contractility of cervical strips from nonpregnant women in this study. No synergistic effect of progesterone could be demonstrated. The passive biomechanical properties (tensile strength, extensibility, stiffness of failure energy) did not change significantly after relaxin incubation. The results obtained in vitro do not suggest an important physiological effect of relaxin on the human nonpregnant cervix.
authors.affiliation: Department of Obstetrics and Gynecology, Aarhus University Hospital, University of Aarhus, Denmark.
authors.forename: L K
authors.initials: LK
authors.lastname: Petersen
authors.forename: I
authors.initials: I
authors.lastname: Vogel
authors.forename: H
authors.initials: H
authors.lastname: Oxlund
authors.forename: A
authors.initials: A
authors.lastname: Forman
authors.forename: N
authors.initials: N
authors.lastname: Uldbjerg
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D002584:Cervix Uteri / Q000187:drug effects*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008875:Middle Aged; D011374:Progesterone / Q000494:pharmacology; D012065:Relaxin / Q000494:pharmacology*; D014590:Uterine Contraction / Q000187:drug effects; D014667:Vasopressins / Q000494:pharmacology
chemical_list: D014667:Vasopressins; D011374:Progesterone; D012065:Relaxin