Human relaxin, a two-chain protein hormone, was synthesized by solid-phase peptide synthesis in combination with a novel thiol-protecting group strategy whereby the three disulfide bonds could be synthesized sequentially and without error. The final product was shown to be homogeneous by reversed-phase high performance liquid chromatography and electrophoresis and had the correct amino acid com...

H2 relaxin activates the relaxin family peptide receptor-1 (RXFP1), a class A G-protein coupled receptor, by a poorly understood mechanism. The ectodomain of RXFP1 comprises an N-terminal LDLa module, essential for activation, tethered to a leucine-rich repeat (LRR) domain by a 32-residue linker. H2 relaxin is hypothesized to bind with high affinity to the LRR domain enabling the LDLa module to...

Sasser JM. The emerging role of relaxin as a novel therapeutic pathway in the treatment of chronic kidney disease. Am J Physiol Regul Integr Comp Physiol 305: R559–R565, 2013. First published July 24, 2013; doi:10.1152/ajpregu.00528.2012.— Emerging evidence supports a potential therapeutic role of relaxin in fibrotic diseases, including chronic kidney disease. Relaxin is a pleiotropic hormone, ...

Pulmonary fibrosis is the common end stage of a number of pneumopathies. In this study, we examined the ability of the human cytokine, relaxin, to block extracellular matrix deposition by human lung fibroblasts in vitro, and to inhibit lung fibrosis in a bleomycin-induced murine model. In vitro, relaxin (1-100 ng/ml) inhibited the transforming growth factor-beta-mediated over-expression of inte...

BACKGROUND Relaxin levels in seminal plasma have been associated with positive effects on sperm motility and quality, and thus having potential roles in male fertility. However, the origin of seminal relaxin, within the male reproductive tract, and the moment of its release in the vicinity of spermatozoa remain unclear. Here, we assessed the longitudinal distribution of relaxin and its receptor...

and Implications One of the primary targets for the biological actions of relaxin is the uterine cervix. The effects of relaxin on this organ include inducing growth and remodeling of connective tissue and cervical cells to accommodate pregnancy and parturition. The related physiological and clinical observations include softening, ripening, and dilating the cervix and facilitating delivery of ...

BACKGROUND Relaxin is a transforming growth factor β1 antagonist. To determine the effects of relaxin on scar reduction, we investigated the scar remodeling process by injecting relaxin-expressing adenoviruses using a pig scar model. METHODS Scars with full thickness were generated on the backs of Yorkshire pigs. Scars were divided into two groups (relaxin [RLX] and Control). Adenoviruses wer...

Spermatogenesis is controlled by FSH, testosterone and paracrine factors produced by Sertoli cells. The knockout of relaxin decreases sperm maturation in mice. Studies from our laboratory have shown that relaxin and its receptor RXFP1 are expressed in rat Sertoli cells, and exogenous relaxin stimulates Sertoli cell proliferation. Relaxin receptors are also detected in the rat germ cells at spec...

Relaxin is a 6-kDa peptide hormone that is secreted from the corpus luteum of the ovary and circulates in the blood during pregnancy in several species, including humans, rats, and mice1 (see Appendix for relaxin ligand and receptor nomenclature). Hisaw and colleagues,2,3 who discovered the hormone, provided the first evidence, albeit structural in nature, that the vasculature is a relaxin targ...

BACKGROUND Renal fibroblasts are important effector cells in tubulointerstitial fibrosis, with experimental antifibrotic strategies focusing on the functional down-regulation of these cells. Several experimental models of fibrosis have provided evidence for the effectiveness of the polypeptide hormone relaxin as a potential antifibrotic agent. This study was conducted to further elucidate the a...