U. Keranen et al., CHANGES IN SUBSTANCE P-IMMUNOREACTIVE INNERVATION OF HUMAN COLON ASSOCIATED WITH ULCERATIVE-COLITIS, Digestive diseases and sciences, 40(10), 1995, pp. 2250-2258
The amount of colonic substance P and substance P-receptors is increas
ed in ulcerative colitis, which may denote that substance-P is involve
d as a neurogenic mediator in the inflammatory process of ulcerative c
olitis. We studied the anatomical distribution of elevated colonic sub
stance P in ulcerative colitis and assessed morphometrically whether t
he changes in substance P correlate with alterations in colonic innerv
ation. Full-thickness specimens of colonic wall were obtained from nor
mal human colons (N = 9) and the most and least affected regions of ul
cerative colitis colons (N = 10) and immunostained for substance P. Su
bstance P immunoreactivity index was calculated by multiplying each in
tensity value by the number of pixels exhibiting this intensity value.
The numbers of substance P-immunoreactive nerve fibers in the lamina
propria were markedly increased, and their fluorescence intensity was
enhanced in ulcerative colitis. The longitudinal muscle layer containe
d substance P-immunoreactive nerve fibers in ulcerative colitis, but n
ot in the controls. The substance P-immunoreactive index (= number x i
ntensity of nerve fibers) was 3.42 +/- 1.49 in controls, 21.19 +/- 7.7
9 in mild ulcerative colitis regions (P < 0.05), and 29.68 +/- 9.81 in
severe ulcerative colitis regions (P < 0.01). Increase in the number
of substance P nerve fibers is in accordance with the hypothesis that
substance P contributes to neurogenic mediation of inflammation in ulc
erative colitis.