title: Vascular actions of relaxin: nitric oxide and beyond.
abstract: The peptide hormone relaxin regulates the essential maternal haemodynamic adaptations in early pregnancy through direct actions on the renal and systemic vasculature. These vascular actions of relaxin occur mainly through endothelium-derived NO-mediated vasodilator pathways and improvements in arterial compliance in small resistance-size arteries. This work catalysed a plethora of studies which revealed quite heterogeneous responses across the different regions of the vasculature, and also uncovered NO-independent mechanisms of relaxin action. In this review, we first describe the role of endogenous relaxin in maintaining normal vascular function, largely referring to work in pregnant and male relaxin-deficient animals. We then discuss the diversity of mechanisms mediating relaxin action in different vascular beds, including the involvement of prostanoids, VEGF, endothelium-derived hyperpolarisation and antioxidant activity in addition to the classic NO-mediated vasodilatory pathway. We conclude the review with current perspectives on the vascular remodelling capabilities of relaxin.
  
  
  
  This article is part of a themed section on Recent Progress in the Understanding of Relaxin Family Peptides and their Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.10/issuetoc.
authors: School of BioSciences, The University of Melbourne, Parkville, VIC, Australia.
authors: C H
authors: CH
authors: Leo
authors: School of BioSciences, The University of Melbourne, Parkville, VIC, Australia.
authors: M
authors: M
authors: Jelinic
authors: School of BioSciences, The University of Melbourne, Parkville, VIC, Australia.
authors: H H
authors: HH
authors: Ng
authors: School of BioSciences, The University of Melbourne, Parkville, VIC, Australia.
authors: S A
authors: 0000-0001-7276-1405
authors: SA
authors: Marshall
authors: Division of Mathematics and Science, Walsh University, North Canton, OH, USA.
authors: J
authors: J
authors: Novak
authors: Department of Physiology, Monash University, Clayton, VIC, Australia.|School of Rural Health, Monash University, Clayton, VIC, Australia.
authors: M
authors: M
authors: Tare
authors: Department of Physiology and Functional Genomics, Department of Obstetrics and Gynaecology, College of Medicine, University of Florida, Gainesville, FL, USA.
authors: K P
authors: KP
authors: Conrad
authors: School of BioSciences, The University of Melbourne, Parkville, VIC, Australia.
authors: L J
authors: LJ
authors: Parry
mesh_terms: D000818:Animals; D004730:Endothelium, Vascular / Q000378:metabolism*; D006801:Humans; D009569:Nitric Oxide / Q000378:metabolism*; D012065:Relaxin / Q000378:metabolism*
chemical_list: D009569:Nitric Oxide; D012065:Relaxin