<p style="text-align: center;">ZHANG Dan, REN Yanbo, WU Huangan, YANG Y anting, WU Lijie, ZHANG Ji, SHI Zheng, MA Xiaopeng</p><p style="text-align: center;">（1Shanghai Research Institute of Acupuncture and Meridian, Shanghai 200030, China; 2 Zhongshan Hospital Affiliated to Fudan University, Shanghai 201907; 3 Shanghai University of Traditional Chinese Medicine, Shanghai 20120）&nbsp;</p><p style="text-align: justify;"><strong>Abstract:</strong>&nbsp; <strong>Objective</strong>:&nbsp; To&nbsp; observe&nbsp; the&nbsp; effects&nbsp; of&nbsp; different-dose&nbsp; herb-partitioned&nbsp; moxibustion&nbsp; (HPM)&nbsp; on colon&nbsp; damage&nbsp; in&nbsp; rats&nbsp; with&nbsp; ulcerative&nbsp; colitis&nbsp; (UC),&nbsp; for&nbsp; selecting&nbsp; the&nbsp; optimal&nbsp; dosage&nbsp; of&nbsp; HPM&nbsp; from&nbsp; the histopathological view. <strong>Methods</strong> The Sprague Dawley (SD) rats were randomized into 7 groups, a normal group, a model group, a Western medication group, and HPM group 1-4, 9 rats per group. UC model was developed by antigen immune plus local chemical stimulation. In the four HPM groups, bilateral “Tianshu” (ST&nbsp; 25)&nbsp; were&nbsp; selected&nbsp; to&nbsp; receive&nbsp; corresponding&nbsp; dosage&nbsp; of&nbsp; HPM&nbsp; treatment&nbsp; varied&nbsp; at&nbsp; cone&nbsp; number&nbsp; and frequency. The general conditions of rats were observed. The pathological changes of colon tissues were examined by using hematoxylin-eosin (HE) staining, periodic acid-schiff (PAS) staining, and high iron diamine-alcian blue (HID-AB) staining. <strong>Results </strong>Compared with the normal group, rats in the model group presented&nbsp; loose&nbsp; stool,&nbsp; some&nbsp; with&nbsp; pus&nbsp; and&nbsp; blood,&nbsp; and&nbsp; slowly&nbsp; increased&nbsp; body&nbsp; weight&nbsp; (P&lt;0.01);&nbsp; gross examination showed that rat colon in the model group had obvious congestion, a couple of white ulcer spots in&nbsp; severe&nbsp; cases;&nbsp; microscopic&nbsp; examination&nbsp; found&nbsp; continuous&nbsp; superficial&nbsp; ulcers&nbsp; in&nbsp; colon,&nbsp; with&nbsp; irregular glandular cavities, swelling and serious inflammatory infiltration in lamina propria and submucosa, and the score of colon tissue damage increased significantly (P&lt;0.01); PAS and HID-AB staining demonstrated that the production of colonic mucus decreased markedly (P&lt;0.01). Compared with the model group, rats in&nbsp; the&nbsp; HPM&nbsp; groups&nbsp; presented&nbsp; increased&nbsp; body&nbsp; weight,&nbsp; formed&nbsp; feces,&nbsp; and&nbsp; improved&nbsp; colon&nbsp; damages, manifested by healed mucosa and mitigated inflammation, and the damage score dropped significantly (P&lt;0.05). PAS and HID-AB staining showed that the production of colonic mucins increased significantly in the HPM groups (P&lt;0.01). The two-level two-factor factorial analysis indicated that both HPM cone number and frequency interacted with colon tissue score and the production of mucus, affecting the efficacy of moxibustion (P&lt;0.05). <strong>Conclusion</strong> HPM at Tianshu (ST 25) promotes the repair of colonic damage and mucus production; from the histopathological view, the number of moxa cone and intervention frequency affect the efficacy of HPM, and HPM once every other day with 2 cones each time should be the optimal choice of dosage.</p><p><strong>Key words</strong>: Acupuncture&nbsp; and&nbsp; moxibustion,&nbsp; Herb-partitioned moxibustion,&nbsp; Ulcerative colitis,&nbsp; HE stains,PAS staining, HID-AB staining, Moxibustion dosage</p><p><br/></p>