[Abstract Title]. - Society for Neuroscience

Support: Supported by CIHR
Title: Bone cancer pain: A new way to fight pain ?
Authors: *V. V. OTIS, L. GENDRON;
Physiologie et Biophysique, Univ. de Sherbrooke, Sherbrooke, QC, Canada
Abstract: In North America, cancer appears in one third of the population and leads to bone
tumour invasion in 60% of cases. Bone metastasis are usually seen in advance stages of cancer
especially those originating from breast or prostate cancer. Chronic pain due to osteosarcoma can
achieve high levels of background and breakthrough pain, therefore increasing the difficulty to
treat patients. As of today, morphine and its derivatives are among the most powerful and
commonly used opioids to alleviate pain. Even with their strong analgesic potency, opioids
acting at mu opioid receptors are often accompanied by various side-effects, possibly including
increased osteolytic activity and bone loss. Over the past few years, compounds activating the
delta opioid receptor (DOPR) were shown to have significant analgesic effects without any
significant side-effects usually associated with narcotics. The aim of this study is to evaluate the
potential roles of selective DOPR agonists for the treatment of bone cancer pain induced by
injection of 30 000 syngenic MRMT-1 cells (mammary carcinoma) in the femur of Sprague-
Dawley rats. As other mammary tumours, our results revealed the presence of DOPR mRNA in
MRMT-1, although at low levels. Thus, DOPR agonists might potentially have an influence on
tumour progression. Fourteen days after cancer induction, rats had develop significant allodynia
in their ipsilateral hindpaw, an effect accompanied by an unilateral activation of glial cells
(astrocyte and microglia) in L2-L4 lumbar spinal cord segments. Our results suggest that this
bone cancer model might be a promising tool to evaluate the role of DOPR agonists for the
treatment of bone cancer-induced pain.
Disclosures: V.V. Otis, None; L. Gendron, None.
Poster
267. Pain: Pain Models II
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 267.7/FF13
Topic: D.08.j. Pain models
Support: NIH R21 NS 055896
P32 NS07375