In this study, we also found that there were no apparent differences in the distribution and intensity of labeling in cervices obtained from nonpregnant women after hysterectomy and women after cesarean section at term (data not shown). Thus available data indicate that, with the exception of the placenta, the use of tissues from nonpregnant humans are satisfactory for identifying specific relaxin-binding cells.
Findings in this study support the view that relaxin-in-duced remodeling of connective tissue has potential for clinical applications. The efficacy of human recombinant relaxin for the treatment of systemic sclerosis is presently under investigation. Relaxin also has potential as a cervical softening agent at term. Two recent clinical trials administered recombinant human relaxin intravaginally at term with the apparent intent of exerting a local effect on the cervix while avoiding possible systemic side effects. Both groups of investigators concluded that the failure of the relaxin treatment to soften the cervix may have been attributable to ineffective absorption of relaxin. There is a need to investigate the influence of relaxin on cervical softening in women and other primates under experimental conditions in which the hormone is administered in such a way as to have ready access to the systemic circulation. buy cheap antibiotics
In summary, this study identifies specific relaxin-binding cells in the cervix, vagina, uterus, mammary glands, nipples, and placenta of the human. They are epithelial cells, smooth muscle cells, and blood vessels in the cervix, vagina, uterus, and mammary nipples; epithelial cells and blood vessels in the mammary glands; skin and sebaceous glands of the nipples; and amnion epithelium, syncytiotro-phoblast, and blood vessels within the placenta. We conclude that the specific relaxin-binding cells probably contain relaxin receptors. Identification of putative relaxin receptors may provide insight into physiological and/or therapeutic roles for relaxin in the human.