relaxininduced

Relaxininduced refers to effects that are produced by the peptide hormone relaxin, or by pharmacological relaxin analogs. In humans, relaxin is a member of the insulin-like peptide family, with relaxin-2 (H2 relaxin) being the principal circulating form during pregnancy and other relaxin family members present in different tissues and species. The term is used to describe physiological and pharmacological responses that arise from relaxin signaling.

Mechanism and targets: Relaxin acts primarily through the G protein–coupled receptor RXFP1, and in some tissues RXFP2 may also participate. Receptor activation elevates cyclic AMP and triggers signaling cascades that lead to vascular smooth muscle relaxation, extracellular matrix remodeling, and changes in connective tissue. This includes upregulation of matrix metalloproteinases and modulation of collagen deposition. Relaxin also promotes vasodilation and can influence renal hemodynamics and natriuresis.

Physiological role: During pregnancy, relaxin contributes to pelvic ligament laxity and cervical remodeling to facilitate parturition. It can influence cardiovascular and renal function, and has anti-fibrotic and anti-inflammatory effects in various tissues in experimental settings.

Clinical context: Relaxin and its analogs, such as serelaxin, have been explored for conditions such as acute heart failure and fibrotic diseases. Although early trials showed potential, later studies yielded mixed or negative results for some indications, and relaxin-based therapies are not broadly approved for these uses. Research continues into identifying responsive patient populations and alternative applications.

See also: relaxin, RXFP1, serelaxin, peptide hormones.