Increase in Cyclic AMP Levels by Relaxin in Newborn Rhesus Monkey Uterus Cell Culture

• Published in: In Vitro Cellular & Developmental Biology 1990-06, Vol.26 (6), p.647-656
• Main Authors: Susan Mukavitz Kramer, Ursula E. M. Gibson, Fendly, Brian M., Marjorie A. Mohler, Drolet, Daniel W., Johnston, Paul D.
• Format: Article
• Language: English
• Subjects: Actins - analysis; Alprostadil - pharmacology; Animals; Animals, Newborn; Antibodies; Antibodies, Monoclonal; Biological and medical sciences; Cell culture techniques; Cell Line; Cell lines; Cell physiology; Cells, Cultured; Colforsin - pharmacology; Cultured cells; Cyclic AMP - metabolism; Epithelial cells; Female; Fundamental and applied biological sciences. Psychology; Hormones; Insulin; Insulin - pharmacology; Insulin-Like Growth Factor I - pharmacology; Insulin-Like Growth Factor II - pharmacology; Macaca mulatta; Molecular and cellular biology; Rapid Communications in Cell Biology; Recombinant Proteins - pharmacology; Relaxin - pharmacology; Responses to growth factors, tumor promotors, other factors; Smooth muscle; Smooth muscle myocytes; Uterus; Uterus - drug effects; Uterus - metabolism
• ISSN: 0883-8364; 2327-431X; 1475-2689
• DOI: 10.1007/BF02624216

A novel relaxin sensitive cell line of apparent smooth muscle origin has been established from a newborn rhesus monkey uterus (NRMU). NRMU cells respond to relaxin, in the presence of 1 μ M forskolin, by producing intracellular adenosine 3', 5'-cyclic monophosphate (cAMP). The increase in cAMP levels is dose, time and cell density dependent, reaching peak levels at 10 min when cells are seeded at 1 × 105 cells/well. Specificity was demonstrated by neutralization of the relaxin activity with anti-relaxin monoclonal and polyclonal antibodies, degradation of cAMP in the presence of phosphodiesterase, and confirmation of the absence of cGMP. Three synthetic analogs of human relaxin generated a dose-related cAMP response as did synthetic native human relaxin. Natural relaxin purified from human corpora lutea tissue also generated a response similar to synthetic human relaxin. Porcine and rat relaxing also increased levels of cAMP. Insulin, but not IGF I or IGF II, was capable of increasing cAMP levels in NRMU cells, however, 200 ng/mL were required to achieve cAMP levels comparable to 6.25 ng/ml relaxin. Combinations of relaxin with insulin, IGF I or IGF II did not increase cAMP levels above levels obtained with relaxin alone. The effect on NRMU cells of other hormones, growth factors and drugs potentially present in cell culture systems or serum samples was evaluated. In combination with relaxin, oxytocin significantly decreased the cAMP production below the levels induced by relaxin alone, whereas progesterone and prostaglandin E2 resulted in additive increases in cAMP. These data suggest that the NRMU cell line is an appropriate target tissue for studying relaxin-mediated biological responses in vitro as well as functioning as the primary component of a relaxin in vitro bioassay.