Dutta S K, Matossian H B, Meirowitz R F, Vaeth J
Department of Medicine, VA Medical Center, Baltimore, Maryland.
Gastroenterology. 1992 Dec;103(6):1833-41. doi: 10.1016/0016-5085(92)91442-7.
To examine the relationship between esophageal acid exposure and development of salivation and heartburn, 15 healthy subjects underwent perfusion of the distal esophagus with varying concentrations of hydrochloric acid, different-osmolality saline solutions, and deionized water. In five study subjects, hydrochloric acid was infused in the body of the stomach only. During the study, timed samples of whole and parotid saliva were collected and analyzed for flow rate and bicarbonate concentration. Only hydrochloric acid concentrations of 20 mmol/L or greater (pH 1.8 or lower) induced a rapid (within 2 minutes) and significant (P < 0.05) increase in salivation. The hydrochloric acid-induced salivation was associated with significant (P < 0.05) increase in bicarbonate secretion in both parotid and whole saliva samples. Intravenous atropine administration completely inhibited hydrochloric acid-induced salivary secretion in all six subjects. Changes in osmolality of saline solution infused in the esophagus and hydrochloric acid infused in the stomach did not significantly alter parotid and whole saliva flow rates. These data suggest that in humans, rapid salivation in response to esophageal mucosal exposure to intraluminal hydrochloric acid is a pH-dependent and osmolality-independent phenomenon that is most likely mediated by pH-sensitive chemoreceptors located in the esophageal mucosa.
为了研究食管酸暴露与唾液分泌及烧心之间的关系，15名健康受试者接受了向食管远端灌注不同浓度盐酸、不同渗透压盐溶液和去离子水的实验。在5名研究对象中，仅在胃体部注入盐酸。在研究过程中，定时采集全唾液和腮腺唾液样本，并分析其流速和碳酸氢盐浓度。仅20 mmol/L或更高浓度的盐酸（pH 1.8或更低）可引起唾液分泌迅速（2分钟内）且显著（P < 0.05）增加。盐酸诱导的唾液分泌与腮腺和全唾液样本中碳酸氢盐分泌显著（P < 0.05）增加相关。静脉注射阿托品可完全抑制所有6名受试者中盐酸诱导的唾液分泌。注入食管的盐溶液渗透压变化以及注入胃内的盐酸变化均未显著改变腮腺和全唾液流速。这些数据表明，在人类中，食管黏膜暴露于腔内盐酸时快速的唾液分泌是一种pH依赖性且与渗透压无关的现象，很可能由位于食管黏膜的pH敏感化学感受器介导。
