CRH receptor subtype 1 (CRHR1) and subtype 2 (CRHR2) on MC are positive and negative modulators, respectively, tuning the degranulation of stress-induced MC [12,13].Psychological stress is a common cause and induces a long-term depressive symptom for IBS, a disorder with an increase of MC and accompanied by intestinal dysbiosis in the gastrointestinal tract [14,15,16,17]. Here, CRHR1 is linked to irritable bowel syndrome.