Objective
To evaluate the expression pattern of activins and related growth factor messenger RNA (mRNA) levels in adenomyotic nodules and in their endometrium. Design: Prospective study. Setting: University hospital. Patient(s): Symptomatic premenopausal women scheduled to undergo hysterectomy for adenomyosis. Intervention(s): Samples from adenomyotic nodules and homologous endometria were collected. Endometrial tissue was also obtained from a control group. Main outcome measure(s): Quantitative real-time polymerase chain reaction (PCR) analysis and immunohistochemical localization of activin-related growth factors (activin A, activin B, and myostatin), binding protein (follistatin), antagonists (inhibin-α, cripto), and receptors (ActRIIa, ActRIIb) were performed. Result(s): Myostatin mRNA levels in adenomyotic nodule were higher than in eutopic endometrium and myostatin, activin A, and follistatin concentrations were higher than in control endometrium. No difference was observed for inhibin-α, activin B, and cripto mRNA levels. Increased mRNA levels of ActRIIa and ActRIIb were observed in adenomyotic nodules compared with eutopic endometrium and control endometrium. Immunofluorescent staining for myostatin and follistatin confirmed higher protein expression in both glands and stroma of patients with adenomyosis than in controls.