Objectives/Hypothesis: Deterioration of aerodigestive tract reflexes such as the esophagoglottal and pharyngoglottal closure reflexes and pharyngeal swallow has been documented in the elderly. However, the effect of aging on the contractile response of the upper esophageal sphincter (UES) to pharyngeal water stimulation has not been studied. The aim of this study was to characterize the pharyngo-UES reflex in the healthy elderly. Methods: We studied nine healthy elderly (7761 y[SD]; four men, five women) and nine healthy young volunteers (2662 y[SD]; four men, five women). AUES sleeve sensor was used to measure the pressure. We tested pharyngeal stimulation induced by rapid pulse and slow continuous injection of water. Results: The volume of water required to stimulate the pharyngo-UES contractile reflex by rapid pulse injection in the elderly (0.56 34 0.1mL) was significantly higher than that in the young (0.16 0.02mL) (P<0.05). In contrast to young subjects, there was no pressure increase in resting UES pressure observed in the elderly for continuous pharyngeal water infusion. In both young and elderly, the threshold volume for the pharyngo-UES contractile reflex was significantly lower than that for pharyngeal swallows. Conclusions: The pharyngo-UES contractile reflex deteriorates with aging. This deterioration is primarily due to abnormalities of the afferent limb of the reflex. Key Words: Upper esophageal sphincter, airway protection, pharyngeal stimulation.

Effect of pharyngeal water stimulation on esophageal peristalsis and bolus transport. Am. J. Phvsiol. 272 (Gastrointest. Liver Physiol. 35): G265-G271, 1997. -Sensory stimuli originating from the pharynx inhibit esophageal peristalsis induced by a dry swallow. Our aims were to determine the effect of these stimuli on esopha-geal bolus transport and esophageal peristalsis induced by swallowing difierent volumes of liquid and semisolid boluses. We studied nine healthy volunteers age 35

目的：明确食管扩张时下食管括约肌发生松弛状态下胃食管反流的发生率。方法：12例健康志愿者在餐前和餐后同时检测食管压力和pH，食管扩张是通过快速和缓慢的气体注射诱发。结果：引起完全的下食管扩约肌松弛的气体阈值量平均为（11.0±1.0）ml。只有极少的松弛伴有继发蠕动。快速注气下食管括约肌的松弛时间为（13.0±1.5）s；慢速注射时食管括约肌的松弛时间是（16.0±2.0）s。由快速阈值量气体注射引超LES松弛并伴有胃食管反流率，在餐后为（22±6）%；缓慢注射时为（23±10）%。对于快速食管扩张，单独的下食管括约肌松弛伴随反流的百分比显著高于伴有继发蠕动的下食管括约肌松弛时出现的胃食管反流情况。结论：（1）胃食管反流可以发生在由食管扩张引起的下食管括约肌松弛期内；（2）食管扩张可以引起不伴随继发蠕动的单纯下食营括约肌松弛：（3）单纯下食菅括约肌松弛时的胃食管反流发生率显著高于伴有继发蠕动的情况。

Pressures generated by the pharyngeal constrictor muscles and proximal esophagus involve acetylcholine-induced muscle contractions. We hypothesized that the pharyngo-esophageal pressure gradient is related to choline acetyltransferase activity. In nine anesthetized cats, hypopharyngeal pressure and proximal esophageal pressure were recorded with a solid state transducer assembly. Enzymatic activities in the thyropharyngeus. cricopharyngeus, and proximal esophageal muscles were measured. Hypopharyngeal pressure was higher than the proximal esophagus (P<0.01), and choline acetyltransferase activity was higher in the cricopharyngeus compared to the proximal esophagus (P<0.05). The pressure gradient between the hypopharynx and proximal esophagus may be influenced by the activity of choline acetyltransferase.

Objective To determine the effect of ageing on length and resting pressure of the upper and lower oesophageal sphincters (UOSs, LOSs). Background The effectiveness of upper and lower oesophageal sphincters (UOSs and LOSs, respectively) in the control of retrograde trans-sphincteric flow is influenced by sphincteric pressure and length. Methods Nine young and nine elderly healthy volunteers were studied. Resting UOS and LOS pressures were measured by sleeve devices and lengths were measured by the station pull-through technique. Results The length of the UOS high pressure zone in the elderly (2.1

目的：观察电针刺足三里穴对大鼠下食管括约肌压力（LESP）的影响以及与血浆胃泌素（GAS）和胃动素（MTL）的关系。方法：将Wistar大鼠40只随机分成5组：对照组、非经非络穴组、足三里穴组、阿托品组和阿托品足三里穴组。应用三通道微细注水式测压管和荷兰UPS-2020型食管测压系统测定大鼠LESP，同时放免法测定血浆GAS和MTL的水平。结果：电针刺大鼠足三里穴和非经非络穴及电针刺停止后，LESP均有明显升高[升高率：62.7±27.0%，131.0±36.4%（0-20 min），122.6±25.9%（21-40 min），P<0.01]，足三里穴组LESP升高明显大于非经非络穴组（2.34±0.69 kPa vs 1.94±0.35 kPa，3.308±0.88 kPa vs 2.30±0.36 kPa，3.17±0.69 kPA vs 2.22±0.40 kPa，P<0.01）。大鼠阿托品ip后LESP明显下降（P<0.01）；在电针刺期间及电针刺后LESP升至正常，升高率明显低于足三里穴组（P<0.01）。电针刺大鼠足三里穴后血浆GAS，MTL水平与对照组相比明显升高（P<0.01）；非经非络穴组升高不明显（P1=0.492，P2=0.104）；阿托品+足三里穴组GAS和MTL比阿托品组明显升高（P1<0.01、P2<0.05）；GAS和MTL变化与LESP呈明显正相关（r1=0.664、r2=0.703，P<0.01）。结论：电针刺对LESP的调控作用具有一定的经络和穴位特异性；胆碱能M受体阻断可部分减弱电针刺足三里的作用，电针刺可以使胆碱能神经阻断大鼠降低的LESP恢复至正常；胃泌素和胃动素可能参动与了电针刺对LESP的调控作用。

目的 评价国产13C-尿素呼气试验药盒诊断幽门螺杆菌（Hp）感染的效果。方法 用多中心随机开放平行对照试验，门诊或病房病人共139例，试验组G9例，对照组70例，经快速尿素酶试验和WS银染色检查确定幽门螺杆菌感染，分别用国产或进口13C-UBT药盒，用质谱仪行13C-尿素呼气试验检测Hp感染，比较不同药盒诊断Hp感染的敏感性、特异性，观察其药物不良反应。结果 试验组诊断Hp的敏感性为100%特异性为88.2%，准确度为95.7%2组比较无显著性差异（P>0.05）。药特不良反诮轻微。结论 用国产13C-尿素呼气试验药盒诊断Hp感染与进口试剂无明显差异，对简单、非侵入性的Hp感染诊断试验安全、可靠。

AIM: To determine the distribution of neurons expressing c-Fos and nitric oxide synthase (NOS) in the central nerve system (CNS) following esophageal acid exposure, and to investigate the relationship between c-Fos and NOS. METHODS: Twelve Wistar rats were randomly divided into two equal groups. Hydrochloric acid with pepsin was perfused in the lower part of the esophagus for 60 min. As a control, normal saline was used. Thirty minutes after the perfusion, the rats were killed and brains were removed and processed for c-Fos immunohistochemistry and NADPH-d histochemistry. Blood pressure (BP), heart rate (HR), and respiratory rate (RR) during the experimental procedures were recorded every 10min. RESULTS: There were no significant differences in BP, HR and RR between the two groups. c-Fos immunoreactivity was significantly increased in rats receiving acid plus pepsin perfusion in amygdala (AM), paraventricular nucleus (PVN), parabrachial nucleus (PBN), nucleus tractus solitarius and dorsal motor nucleus of vagus (NTS/DMV), nucleus ambiguous (NA), reticular nucleus of medulla (RNM) and area postrema (AP). NOS reactivity in this group was significantly increased in PVN, PBN, NTS/DMV, RNM and AP. c-Fos and NOS had significant correlation between PVN, PBN, NTS/DMV, RNM and AP. CONCLUSION: Acid plus pepsin perfusion of the esophagus results in neural activation in areas of CNS, and NO is likely one of the neurotransmitters in some of these areas.