Background: Central mediated abdominal pain syndrome (CAPS) related functional gastrointestinal disorders (FGIDs) is a commonly seen disease. Although the efficacy of antidepressants in treatment of CAPS has been reported, yet there is still lack of typical representative drugs and sufficient clinical data. Aims: To evaluate the efficacy of duloxetine in CAPS. Methods: A total of 143 patients with CAPS from Jan. 2017 to Dec. 2019 at Qingdao Municipal Hospital were enrolled and randomly divided into duloxetine group and placebo group. Brief pain inventory (BPI) was used to evaluate the efficacy. Results: Compared with placebo group, duloxetine significantly improved the average pain, the most painful in the past 24 hours, as well as the minimum pain and present pain in the patients with CAPS, and the impact on daily life, emotion, interest in life, walking ability, sleep, interpersonal relationship, working was significantly improved in duloxetine group. 6.8% of patients in duloxetine group had treatment-induced adverse events, including nausea, dry mouth, constipation, and headache. Conclusions: Duloxetine can improve CAPS, and the safety in use is well.

AIM:To explore whether histamine can regulate the expression of early growth response factor-1 (Egr-1) in the cerebral cortex astrocytes.METHODS:Normal wild-type (WT) mice, histidine decarboxylase knockout ( HDC-KO) mice and histamine treated HDC-KO mice were sacrificed for extracting the total RNA of the cerebral cortex. Primary cultured rat cortical astrocytes were treated with histamine at concentrations of 10 -8 , 10 -7 , 10 -6 , 10 -5 or 10 -4 mol/L for 15, 30, 60, 120 or 240 min.H1 or H2 receptor antagonists were pretreated for 15 min before histamine treat-ment.After histamine treatment, the cell total RNA or protein was extracted.The expression of Egr-1 at mRNA and protein levels was determined by real-time PCR and Western blot.RESULTS:The mRNA level of Egr-1 in cerebral cortex of HDC-KO mice was significantly lower than that in WT mice, while exogenous histamine induced the mRNA expression of Egr-1 in HDC-KO mice.In cultured astrocytes, histamine induced the mRNA expression of Egr-1.The maximum increase in the mRNA level of Egr-1 was produced by histamine at concentration of 10 -5 mol/L.In addition, histamine-induced Egr-1 mRNA accumulation peaked at 30 min after commencing stimulation, while histamine significantly increased Egr-1 protein expression at 60 min.Furthermore, histamine-induced Egr-1 expression was inhibited by H1 receptor antagonist but not H2 receptor antagonist.CONCLUSION:Histamine up-regulates the Egr-1 expression in cerebral cortex and cultured astrocytes, which may attribute to H1 receptor activation.