CRH and irritable bowel syndrome: Baseline levels of plasma noradrenaline before injection were significantly higher in IBS patients (215.3 ± 92.9 pg/ml) than in controls (115.4 ± 39.6 pg/ml) (P = .001) and still showed a significant difference between IBS patients and controls after CRH injection (P = .001) (Fig 4A).