Hydroxymethyl cellulose

The mice were anesthetized using 1.5% isoflurane (4% for induction) in an oxygen/nitrous oxide 30%/70% mixture. Dorsal incisions were made, bilateral oophorectomy was performed, and wounds were stapled. Animals were monitored carefully during the recovery phase and 5 mg Rimadyl/kg bodyweight was administered s.c. for pain relief. Three weeks after ovariectomy, the UF tissue pieces, were transplanted s.c. using a trocar. During the same surgery, mice were supplemented s.c. with (60 day release estrogen) E2 pellets (Innovative Research of America, Sarasota, FL, USA). Animals received EC313 0.1 mg/kg, N = 6, or 1 mg/kg, N = 6), or UPA (5 mg/kg, N = 5) by subcutaneous injection (s.c) for five days per week for 8.5 weeks. E2 control animals received E2 + vehicle (N = 5). 0.2% hydroxymethyl cellulose (Sigma Aldrich, St. Louis, MO) in phosphate buffered saline (Life technologies, Carlsbad, CA) was used as vehicle. At termination of the study animals were weighed, sacrificed, and the uterus and fibroid xenografts were excised and weighed. Tissues were harvested, fixed in 10% formalin, and processed for immunohistochemistry (IHC) for ER, PR, Ki67, desmin and α-SMA.