Fig. 1

Application of rhBMP-2 in rat model of posterior lateral arthrodesis triggers changes in the PNS and CNS. a Illustration depicting placement of rhBMP-2/ACS next to the spine. Of the PNS structures, only the dorsal rami as well as nerves innervating the facet joint (not shown) are likely to make direct contact with rhBMP-2/ACS. b QPCR analysis of RNA isolated from ipsilateral and contralateral DRGs of rats 24 h after implantation of either rhBMP-2/ACS or vehicle/ACS. DRG samples were assessed using markers of inflammation (Cox-2 and IL-1β), nerve injury (ATF-3), nociceptive activity (MCP-1) and BMP-2 signaling (Smad-7 and ID-1) (mean ± SEM, n = 5, *p < 0.05, **p < 0.01). c QPCR analysis of RNA isolated from ipsilateral and contralateral dorsal horn spinal cord from the same animals as in 1B, 24 h after implantation of either rhBMP-2/ACS or vehicle/ACS. Increased expression of c-fos mRNA, but not dynorphin mRNA was detected in ipsilateral DSC of rhBMP-2/ACS implanted animals (mean ± SEM, n = 5*, p < 0.05, **p < 0.01). d QPCR analysis of RNA isolated from DRG explant cultures where L4 and L5 DRG from one side of a rat were combined and treated overnight in rhBMP-2 medium while L4/L5 DRG from the other side of the same animal were bathed in control medium (mean ± SEM, n = 4, *p < 0.05)