Description
Relaxin is a peptide hormone that belongs to the insulin family.
The main function of this hormone is the relaxation of smooth musculature. Relaxin was commonly known to be produced in the ovaries, which was mainly detectable during pregnancy and birth. More recently however, investigations have shown, that synthesis of relaxin could also occur in the placenta, endometrium, mammary glands, or prostate. This hormone is known to be multi-functional, since the binding of relaxin to specific receptors has been observed in the brain, uterus and the heart.
In particular, studies show that relaxin: (i) promotes dilation of blood vessels in several organs and tissues; (ii) has a chronotropic action on the heart; (iii) inhibits the stimulation of endothelin-1, the most potent vasoconstrictor in heart failure; (iv) inhibits the release of histamine by mast cells, thus being able to counteract experimental allergic asthma; (v) depresses aggregation of platelets and their release by megakaryocytes; (vi) influences the secretion of hormones by the pituitary gland; and (vii) contributes to the regulation of fluid balance.
