EFFECTS OF INTRALUMINAL ACIDIFICATION ON ESOPHAGEAL MOTOR-ACTIVITY

This study assessed the effect of prolonged intraluminal acidification on the motor activity of the entire oesophageal body (under controlle d conditions). Intraoesophageal pressures were recorded in 13 endoscop y negative subjects with gastro-oesophageal reflux disease in whom sal ine, HCl 0.1 N, and saline solutions were infused (1.5 ml/min) blindly in the oesophageal body, 6 cm distal to the upper oesophageal sphinct er for three consecutive periods of 45 minutes each. These findings we re compared with those of a control group. Intraoesophageal acidificat ion caused an increase in the deglutition frequency (p<0.02), the occu rrence of multipeaked waves (p<0.04) as well as a decrease of the prop agating velocity (p<0.04) of the primary peristaltic contractions. Fur thermore, intraoesophageal acidification determined an increase, at al l levels of the oesophagus, of the duration (p<0.04)and, more noticeab le in the proximal oesophageal body, of the amplitude (p<0.02) of prim ary peristaltic contraction waves. In conclusion prolonged intraoesoph ageal acidification can considerably affect frequency of deglutition, morphology, and propagating patterns of primary peristaltic contractio ns. This study shows that these effects are independent from volume di stension of the oesophagus and supports the presence of acid sensitive receptors in the oesophageal mucosa.