Increased evidence suggests that dopamine acts as an important regulator of immune function. A substantial amount of dopamine exists in the gastrointestinal tract, especially in colonic lumen. Decreased dopamine level has been reported in the colonic mucosa of ulcerative colitis patients. Therefore, the investigators suppose that colonic dopamine could involve in the ulcerative colitis and play an important role. This study aims to explore the role of dopamine in ulcerative colitis and underlying mechanism, which will provide a rationale for diagnosis and treatment of the ulcerative colitis.

This study is a case-control clinical study. 30 patients with non-ulcerative colitis examined by endoscopy were selected as the control group. According to the inclusion and exclusion criteria, 30 patients with ulcerative colitis were determined. The baseline data of patients were recorded objectively: name, sex, age, vital signs, body weight and stool condition (frequency, character, etc.). Some laboratory examination results (blood routine, fecal routine and fecal culture, liver function, blood coagulation function, electrolyte, etc.), ulcerative colitis lesion range, ulcerative colitis classification and related history (common disease, treatment history and life history). Colonic mucosal tissue samples of patients with ulcerative colitis and control group were obtained by colonoscopic biopsy. The degree of inflammation was evaluated by related inflammatory factors via ELISA. The changes of dopamine system was detected by HPLC-ECD, Western Blot and immunohistochemistry. This study aims to provide new diagnostic and therapeutic basis, select appropriate drug delivery through clarify the effect and mechanism of local dopamine on colitis.

Inclusion Criteria:

1. Patients with or without ulcerative colitis diagnosed by endoscopy and histopathology
2. Negative bacterial culture in stool
3. Written informed consent

Exclusion Criteria:

1. Patients with cardiovascular and cerebrovascular diseases, or patients with severe impairment of liver, kidney and hematopoietic system
2. Mental patients
3. Hemorrhagic diseases
4. Platelet count < 50 × 10 ^ 9 / L
5. Allergic constitution
6. unable to tolerate or cooperate with endoscopy
7. Patients with serious complications, such as intestinal obstruction, intestinal perforation, toxic colonic dilatation, colorectal cancer, etc.
8. Pregnant or lactating women

Patients with oulcerative colitis diagnosed by endoscopy and histopathology