MCC and colitis: Here, analysis of c-Fos expression indicated a significant reduction in the overall MCC activation levels in hM4Di-expressing DSS-treated mice that were injected with CNO followed by noxious CRDs, compared to animals that only received noxious CRDs, demonstrating that chemogenetic suppression could effectively reduce MCC neuronal activation induced by noxious visceral mechanical stimulation in the colitis animals (DSS + noxious CRDs: 8933 ± 785 vs DSS + noxious CRDs + CNO: 2326 ± 342 counts/mm3, p = 0.0009; Fig. 3B, examples in Fig. 3D).