Psychological stress and gastric emptying in normal subjects

Effects of corticotropin-releasing hormone on gastric electrical activity and sensorimotor function in healthy volunteers: a double-blinded crossover study

Biopsychosocial factors are associated with disorders of gut-brain interaction (DGBI) and exacerbate gastrointestinal symptoms. The mechanisms underlying pathophysiological alterations of stress remain unclear. Corticotropin-releasing hormone (CRH) is a central regulator of the hormonal stress response and has diverse impact on different organ systems. The aim of the present study was to investigate the effects of peripheral CRH infusion on meal-related gastrointestinal symptoms, gastric electrical activity, and gastric sensorimotor function in healthy volunteers (HVs). In a randomized, double-blinded, placebo-controlled, crossover study, we evaluated the effects of CRH on gastric motility and sensitivity. HVs were randomized to receive either peripheral-administered CRH (100 µg bolus + 1 µg/kg/h) or placebo (saline), followed by at least a 7-day washout period and assignment to the opposite treatment. Tests encompassed saliva samples, gastric-emptying (GE) testing, body surface gastric mapping (BSGM, Gastric Alimetry; Alimetry) to assess gastric myoelectrical activity with real-time symptom profiling, and a gastric barostat study to assess gastric sensitivity to distention and accommodation. Twenty HVs [13 women, mean age 29.2 ± 5.3 yr, body mass index (BMI) 23.3 ± 3.8 kg/m2] completed GE tests, of which 18 also underwent BSGM measurements during the GE tests. The GE half-time decreased significantly after CRH exposure (65.2 ± 17.4 vs. 78.8 ± 24.5 min, P = 0.02) with significantly increased gastric amplitude [49.7 (34.7-55.6) vs. 31.7 (25.7-51.0) µV, P < 0.01], saliva cortisol levels, and postprandial symptom severity. Eleven HVs also underwent gastric barostat studies on a separate day. However, the thresholds for discomfort during isobaric distensions, gastric compliance, and accommodation did not differ between CRH and placebo.NEW & NOTEWORTHY In healthy volunteers, peripheral corticotropin-releasing hormone (CRH) infusion accelerates gastric-emptying rate and increases postprandial gastric response, accompanied by a rise in symptoms, but does not alter gastric sensitivity or meal-induced accommodation. These findings underscore a significant link between stress and dyspeptic symptoms, with CRH playing a pivotal role in mediating these effects.

Efeito do tratamento da depressão sobre o esvaziamento gástrico

O esvaziamento gástrico foi medido por meio de refeição sólida marcada com 99mTc em 11 pacientes que atendiam os critérios de "depressão maior" do DSM-III-R antes e após o tratamento com fluoxetina (20 a 40mg por dia) durante nove semanas. Após o tratamento não se observou redução no tempo para o esvaziamento gástrico de metade da refeição de prova (T1/2) em relação a antes do tratamento. Pode-se, no entanto, separar os pacientes em dois subgrupos: 1) Os que exibiram resposta ao antidepressivo (redução do escore da Escala de Depressão de Hamilton >50%) e apresentaram redução significativa do T1/2 (p<0,001) e 2) Os pacientes que, sem resposta ao tratamento (redução do escore da Escala de Depressão de Hamilton £50%), não apresentaram redução do T1/2 (p>0,10). Concluímos que a alteração da velocidade do esvaziamento gástrico pode estar correlacionada à resposta ao tratamento antidepressivo e que sua redução ou aumento não pode ser atribuída à ação farmacológica da fluoxetina sobre o estômago, mas antes ao efeito da melhoria da depressão sobre a motilidade gástrica.