Azpiroz F
Digestive System Research Unit, Hospital General Vall d'Hebron, Autonomous University of Barcelona, Spain.
Eur J Gastroenterol Hepatol. 1998 Sep;10(9):733-5.
Gastric function is finely modulated by a series of neurological mechanisms, so that gastric digestion is normally not perceived. Alteration of these control mechanisms may lead to different situations, which are frequently associated with symptoms. An impaired tonic contraction of the proximal stomach, that is, an impaired gastric tone, results in gastroparesis. Patients with functional dyspepsia, and also patients with achalasia, have impaired meal accommodation of the stomach. Interestingly, patients with functional dyspepsia may also have a sensory dysfunction, and both dysfunctions could play a synergistic role. However, the sensory dysfunction in dyspepsia, particularly the types of afferent fibres affected, and the mechanisms of impaired accommodation, still remain to be characterized. Evaluation of gastric function has been approached using the barostat. However, the barostat has limitations and potential technical pitfalls that require proper attention. Meal ingestion induces a variety of reflexes and the net result is a relaxation of the stomach. However, gastric reflexes can be best evaluated with the stomach empty, when the stimuli are applied at a different site. Nevertheless, altered reflex responses may be difficult to interpret. For instance, absent or decreased relaxatory responses may equally correspond to a gastroparetic stomach without tone or to a dyspeptic stomach unable to relax. In this context, it may be important to measure basal tone. Distension of the stomach by means of the barostat has been also used to test gastric sensitivity. However, recent studies have shown that perception of gastric distension relays on stimulation of tension receptors; since wall tension depends on both pressure and volume, distension with the barostat may be difficult to standardize. Hopefully, a battery of tests may become available in the near future for a complete neuromuscular evaluation of the gut.
胃功能受到一系列神经机制的精细调节，因此正常情况下不会察觉到胃的消化过程。这些控制机制的改变可能导致不同情况，这些情况常伴有症状。胃近端的紧张性收缩受损，即胃张力受损，会导致胃轻瘫。功能性消化不良患者以及贲门失弛缓症患者的胃对进餐的适应性均受损。有趣的是，功能性消化不良患者可能还存在感觉功能障碍，这两种功能障碍可能起协同作用。然而，消化不良中的感觉功能障碍，尤其是受影响的传入纤维类型以及适应性受损的机制，仍有待明确。一直使用恒压器来评估胃功能。然而，恒压器存在局限性和潜在的技术缺陷，需要予以适当关注。进餐会引发多种反射，最终结果是胃放松。然而，当胃排空且在不同部位施加刺激时，胃反射能得到最佳评估。尽管如此，反射反应的改变可能难以解释。例如，松弛反应缺失或减弱可能同样对应于无张力的胃轻瘫胃或无法放松的消化不良胃。在这种情况下，测量基础张力可能很重要。通过恒压器使胃扩张也已用于测试胃敏感性。然而，最近的研究表明，对胃扩张的感知依赖于张力感受器的刺激；由于壁张力取决于压力和容积，使用恒压器进行扩张可能难以标准化。有望在不久的将来能有一系列测试用于对肠道进行全面的神经肌肉评估。
