title: Does serelaxin treatment alter passive mechanical wall properties in small resistance arteries?
abstract: The peptide hormone relaxin is recognized for its connective tissue remodeling actions in the reproductive tract during pregnancy and parturition, but it also has vascular remodeling actions independent of pregnancy. Recombinant human relaxin (serelaxin) treatment in male and non-pregnant female rodents enhances passive arterial compliance in the renal vasculature. This review focuses on serelaxin's actions on passive mechanical wall properties in small arteries and highlights the diversity of responses to serelaxin treatment in rodents. Different experimental approaches (duration of serelaxin treatment, rat strain, age) and animal models of disease (obesity, hypertension) will be considered. Most studies in young rodents demonstrate that serelaxin treatment fails to alter passive compliance in resistance-size arteries (mesenteric and femoral arteries and cerebral parenchymal arterioles), suggesting that serelaxin's beneficial effects are minimal in healthy animals. Short-term serelaxin treatment (5d) in aged, obese, and spontaneously hypertensive rats (SHRs) is largely without effect on passive mechanical wall properties. However, a longer duration of serelaxin treatment in SHRs (14d) enhances passive compliance in large muscular arteries as well as resistance-size arteries. In conclusion, serelaxin is capable of vascular remodeling. Its actions are vascular bed-dependent, more prominent in disease, and likely requires a longer duration of treatment to be effective.
authors.affiliation: School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Maria
authors.initials: M
authors.lastname: Jelinic
authors.affiliation: School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Nicola
authors.initials: N
authors.lastname: Kahlberg
authors.affiliation: School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Parry
authors.affiliation: Department of Physiology, Monash University, Parkville, Victoria, Australia.|School of Rural Health, Monash University, Parkville, Victoria, Australia.
authors.forename: Marianne
authors.initials: M
authors.lastname: Tare
mesh_terms: D000818:Animals; D001158:Arteries / Q000187:drug effects* / Q000502:physiology; D001696:Biomechanical Phenomena / Q000187:drug effects; D003187:Compliance / Q000187:drug effects*; D004195:Disease Models, Animal; D006801:Humans; D007668:Kidney / Q000098:blood supply; D051381:Rats; D011994:Recombinant Proteins / Q000494:pharmacology / Q000627:therapeutic use; D012065:Relaxin / Q000494:pharmacology / Q000627:therapeutic use*; D012107:Research Design; D013997:Time Factors
chemical_list: D011994:Recombinant Proteins; C577649:serelaxin protein, human; D012065:Relaxin
keywords: RXFP1; arterial compliance; relaxin; vascular remodeling