Altered uterine contractility in response to β-adrenoceptor agonists in ovarian cancer

We aimed to prospectively examine β-adrenoceptor-mediated uterine contractility in women suffering from gynecological malignancies. Myometrial specimens were obtained from non-pregnant women undergoing hysterectomy for benign gynecological disorders, and ovarian, endometrial, synchronous ovarian-endometrial, and cervical cancer. Contractions of myometrial strips in an organ bath before and after cumulative dosages of β₂- and β₃-adrenoceptor agonists with preincubation of propranolol, SR 59230A, and butoxamine were studied. All agonists induced a dose-dependent attenuation for uterine contractility in endometrial or cervical cancer, similar to that observed in the reference group. Contradictory effects were observed for ovarian cancer alone or in combination with endometrial cancer. CL 316243 or ritodrine abolished the relaxation, whereas BRL 37344 increased the uterine contractility in ovarian cancer. Moreover, β-adrenoceptor antagonists caused varied effects for β₂- or β₃-adrenoceptor agonists. Our experiments demonstrate that ovarian cancer, alone or as synchronous ovarian-endometrial cancer, substantially alters uterine contractility in response to β-adrenoceptor agonists.