Colocalization of substance P (SP) and isolectin B4-binding (IB4) neurons with calcitonin gene-related peptide (CGRP) neurons in dorsal root ganglion (DRG).

(A, B) Double-labeling immunofluorescent staining was performed with anti-CGRP (A in red) and anti-SP (B, in green) antisera on DRG sections. Some of CGRP(+) neurons were colocalized with SP(+) neurons (arrow in A and B), whereas there were CGRP(−)/SP(+) neurons (asterisk in A and B). (C) The graph shows the colocalization ratios of SP(+)/CGRP(+) (open bar, n = 5) and CGRP(+)/SP(+) neurons (filled bar, n = 5). (D, E) These graphs show the coexpression of CGRP(+) (D in green) and IB4(+) (E in red) neurons on DRG sections. There was limited colocalization of IB4(+)/CGRP(+) neurons (arrow in D, E), and there was CGRP(−)/IB4(+) neurons (asterisk in D, E). (F) The graph shows the colocalization ratio of IB4(+)/CGRP(+) (open bar, n = 5) and CGRP(+)/IB4(+) neurons (filled bar, n = 5). Bar, 50 µm.