Effects of LNG-IUS on nerve growth factor and its receptors expression in patients with adenomyosis

Abstract

The levonorgestrel-releasing intrauterine system (LNG-IUS) is effective in the treatment of dysmenorrhea associated with adenomyosis. However, the mechanism of pain relief of LNG-IUS in patients with adenomyosis is unclear. We aimed to investigate the effects of LNG-IUS on the expression of nerve growth factor (NGF) and its receptors, NGFR p75 and TrkA in patients with adenomyosis. Endometrial and myometrial tissues were prepared from 17 LNG-IUS-treated patients and 15 hormonally untreated patients who had undergone hysterectomies for adenomyosis. Immunohistochemistry with antibodies against NGF, NGFR p75, and TrkA, was performed. The expression of NGF, NGFR p75, and TrkA in endometrium and myometrium of LNG-IUS-treated patients was significantly decreased compared to those of hormonally untreated patients. Our findings may indicate that the suppression of NGF and its receptors by LNG-IUS is another possible mechanism of relieving pain in patients with adenomyosis.

Keywords::

• Nerve growth factor
• NGF receptor p75
• NGF-specific tyrosine kinase receptor-A (TrkA)
• immunohistochemistry
• adenomyosis

Declaration of interest: This study was supported by a faculty research grant of Yonsei University College of Medicine for 2008 (Grant No. 6-2008-0112). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.