HTR1A and irritable bowel syndrome: The changes in 5-HT and its metabolic rate and 5-HT1A receptor, as well as PKA, pCREB and BDNF expression after treatment with resveratrol support the fact that resveratrol produces anti-IBS-like effects via regulation of 5-HT1A receptor-dependent PKA-CREB-BDNF signaling.