Inflammatory pain persisting for four or six weeks does not reduce exploratory behavior during the elevated zero maze or the open field test, nor results in locomotor deficits. White-filled data points in the REC group indicate where REC n<4 and was not compared to SAL and CFA in ordinary one-way ANOVAs or Kruskall-Wallis tests. Lines compare SAL vs. CFA, and SAL vs. REC, line ending in a bracket compares SAL vs. CFA+REC together.
A: Schematic of experimental design.
B: Paw withdrawal thresholds in the Hargreaves assay for thermal hyperalgesia by mice injected with CFA and sustaining thermal hyperalgesia for four weeks (n=10), compared with mice injected with saline (n=10).
C: Distance traveled in the open field by mice injected with CFA and sustaining thermal hyperalgesia for four weeks (n=10), compared with mice injected with saline (n=10).
D: Paw withdrawal thresholds in the Hargreaves assay for thermal hyperalgesia by mice injected with CFA and sustaining thermal hyperalgesia for six weeks (n=8), compared with mice injected with CFA which recovered (n=4), and with mice injected with saline (n=12).
E: Distance traveled in the open field by mice injected with CFA and sustaining thermal hyperalgesia for six weeks (n=6), compared with mice injected with CFA which recovered (n=4), and with mice injected with saline (n=11).
F: Entries into the open arms of the EZM by mice injected with CFA and sustaining thermal hyperalgesia for four weeks (n=10), compared with mice injected with saline (n=10).
G: Time spent in the open arms of the EZM by mice injected with CFA and sustaining thermal hyperalgesia for four weeks (n=10), compared with mice injected with saline (n=10).
H: Entries into the open arms of the EZM by mice injected with CFA and sustaining thermal hyperalgesia for six weeks (n=8), compared with mice injected with CFA which recovered (n=4), and with mice injected with saline (n=12).
I: Time spent in the open arms of the EZM by mice injected with CFA and sustaining thermal hyperalgesia for six weeks (n=8), compared with mice injected with CFA which recovered (n=4), and with mice injected with saline (n=12).
J: Entries into the center of the OFT by mice injected with CFA and sustaining thermal hyperalgesia for four weeks (n=10), compared with mice injected with saline (n=10).
K: Time spent in the center of the OFT by mice injected with CFA and sustaining thermal hyperalgesia for four weeks (n=10), compared with mice injected with saline (n=10).
L: Entries into the center of the OFT by mice injected with CFA and sustaining thermal hyperalgesia for six weeks (n=6), compared with mice injected with CFA which recovered (n=4), and with mice injected with saline (n=11).
M: Time spent in the center of the OFT by mice injected with CFA and sustaining thermal hyperalgesia for six (n=6), compared with mice injected with CFA which recovered (n=4), and with mice injected with saline (n=11).