Figure 4
From: Inter-strain differences of serotonergic inhibitory pain control in inbred mice
Nociception in the formalin tests and c-Fos upregulation in the dorsal horn in four inbred mouse strains. A. Chemical nociceptive sensitivity of C57BL/6J, 129 Sv, DBA/2J and Balb/c mice. Data are means ± s.e.m of n = 8 in each group. Nociception was assessed by recording the time course of paw licking behavior after injection of formalin into a hindpaw and B comparison of the total licking times. C-F Representative results of c-Fos immunoreactivity in the dorsal horn of the spinal cord 2 hours after injection of formalin into the left hindpaw. c-Fos IR neurons were counted of each four C57BL/6J, 129 Sv, DBA/2J and Balb/c mice. Scale bar: 200 μm. G Quantitative result of c-Fos IR neurons after formalin injection. The asterisk indicates statistically significant differences between strains, with P < 0.05.