3.2.2 Co-localization of EP4 and COX-1 in dorsal root ganglia (DRG)
When the DRG cells were stained with two antibodies for both of EP4 and COX-1, there was a co-expression of the two proteins. An example of EP4 and COX-1 dual labelling is shown in figure 7A using confocal imaging of DRG neurons EP4 specific antibody (red) and the COX-1 specific antibody (green). The frequency histogram of cell size derived for six ganglia in figure (7B) shows that 36% of DRG neurons express both EP4 receptor and the COX-1 proteins, with a mean cell area of 849.1± 22.4μm2.The dual labelling occurred mainly in small neurons (77.8%, <1000 μm2), with fewer medium (20.1%, 1,000-2,000 μm2) and large neurons (2.1%, >2,000 μm2) labelled.