Rectal Mucosal Adrenergic Innervation and Enterochromaffin Cells in Ulcerative Colitis and Irritable Colon

Abstract

Rectal mucosal biopsies of 13 patients suffering from ulcerative colitis, 7 patients presenting symptomatology typical of irritable colon, and 7 control persons were studied by the recently introduced glyoxylic-acid-induced fluorescence histochemical method. In ulcerative colitis, compared to control specimens: 1) the density of the adrenergic nerve network was significantly pronounced; 2) the mean diameter of the varicosities and the proportional share of large varicosities were increased, as well as the number of varicosities per a given length of an axon; 3) the intensity of the fluorescence of varicosities of comparable size was significantly increased; 4) the number of enterochromaffin cells was significantly decreased. In irritable colon, compared to control specimens, the number of enterochromaffin cells was significantly increased. These findings suggest that biogenic amines are somehow involved in both ulcerative colitis and irritable colon. The fluorescence histochemical method used was found sensitive, specific, and suitable for comparative studies on human clinical material.

Differential signal pathway activation and 5-HT function: the role of gut enterochromaffin cells as oxygen sensors

“…Increased 5-HT secretion (2,17) and decreased levels of 5-HT transporters (SERT) (8) have been noted in IBD, the latter, a reuptake mechanism facilitating degradation of 5-HT. In diarrhea-dominated IBS (D-IBS), the EC cell number is also increased (31), which is accompanied by elevated postprandial plasma 5-HT (1). In addition, SERT is downregulated in D-IBS (8).…”

Involvement of c-Src and Protein Kinase Cδ in the Inhibition of Cl-/OH- Exchange Activity in Caco-2 Cells by Serotonin

“…Although 5-HT has been known to play a major role in regulating a number of physiological functions in the GI tract, elevated levels of serotonin have been implicated in the pathophysiology of disease states such as carcinoid syndrome (7), celiac disease (28), irritable colon (29), and dumping syndrome (30). Previous studies have shown that 5-HT administration in vivo induces Cl Ϫ secretion in the rabbit small intestine (31) and acts as a mediator of diarrhea in patients with carcinoid syndrome associated with a net secretion of water and electrolytes (32).…”

The Function of 5‐HT3 Receptors on Colonic Transit in Rats

“…IBS is considered to be stress-related functional bowel disease, which is characterized by abdominal pain and altered bowel habit (12). The symptoms of IBS are correlated to I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I altered bowel motility (9) and the number of enterochromaffin cells is increased in the rectal mucosa of IBS patients (10). These results suggest that 5-HT is involved in the pathogenesis of this disorder.…”