不同时间四氢叶酸钙解救对大剂量甲氨喋呤化疗导致的大鼠肠黏膜损伤保护作用的研究

目的 观察不同时间四氢叶酸钙(CF)解救对大剂量甲氨喋呤(HD-MTX)化疗导致的大鼠肠黏膜组织形态学的改变、病死率及腹泻情况,探讨CF使用的适宜时机.方法 6周龄Wistar大鼠分5组.A组:正常对照组;B组:空白对照组;C、D、E组:实验组,分剐于腹腔注射HD-MTX后12、24、30h予以CF解救.观察各组大鼠病死率、腹泻情况及空肠大体形态,标本测肠黏膜绒毛长度和隐窝深度.结果 A组无腹泻,B、C、D、E组第2天开始出现腹泻,第3天全部出现腹泻,其中B、E组腹泻严重.A组肠壁无充血水肿,B、C、D、E组肠壁充血水肿变薄,其中B、E组最重.A组无死亡,C、D组各死亡3只,E组死亡4只,B组死亡6只.B、C、D、E组肠黏膜绒毛变短,肠隐窝变浅,与A组比较差异有统计学意义(P<0.05);C、D组与B组比较差异有统计学意义(P<0.05);B、E组间差异无统计学意义(P>0.05).结论 HD-MTX可致大鼠严重肠黏膜损伤,适宜时间CF解救可减轻HD-MTX对大鼠肠黏膜的损伤,但不能完全阻止其损伤.     

重组人生长激素（rhGH）对肠梗阻大鼠肠黏膜屏障和免疫屏障的实验研究

目的探讨重组人生长激素（rhGH）对肠梗阻大鼠肠黏膜屏障和免疫屏障的保护作用。方法结扎SD大鼠末端回肠,使肠腔狭窄75％,制作成不完全性肠梗阻动物模型;并应用rhGH6d（每日1次）,观察其回肠黏膜形态学、回肠液sIgA改变及肠道细菌移位情况。结果肠梗阻时,大鼠回肠壁表现为肌层变薄,黏膜厚度减少,肠绒毛变短、变细;回肠液中sIgA浓度减少及细菌移位数量增加;应用rhGH后,回肠黏膜厚度、肠绒毛结构保持相对完整,回肠液中sIgA浓度升高,细菌移位减少。结论肠梗阻时,大鼠肠道黏膜屏障和免疫屏障功能受损,给予外源性rhGH可以较好保护受损肠道的黏膜屏障和免疫屏障功能。     

谷氨酰胺和表皮生长因子对新生鼠坏死性小肠结肠炎的影响

目的探讨谷氨酰胺(Gln)和表皮生长因子(EGF)对新生鼠坏死性小肠结肠炎(NEC)肠黏膜修复的影响。方法新生1日龄Wistar大鼠40只随机分为4组,A组(正常对照组),B组(NEC模型组),C组(NEC Gln),D组(NEC EGF Gln)。建立NEC模型,4 d后分别取近回盲段2~3 cm肠道组织固定、包埋、切片。HE染色光镜下作病理学检查,应用免疫组织化学技术检测肠黏膜增殖细胞核抗原(PCNA)的表达,TUNEL法检测肠黏膜细胞凋亡。结果B组HE染色切片见肠黏膜损伤,病理评分的中位积分为3分;C、D组损伤程度较轻,病理评分的中位积分为1分。B组PCNA阳性细胞数低于A组(P<0.01);C、D组PCNA阳性细胞数高于B组(P<0.01);且D组PCNA阳性细胞数高于C组(P<0.05)。B组肠黏膜细胞凋亡数高于A组(P<0.01);C、D组肠黏膜细胞凋亡数低于B组(P<0.01);且D组肠黏膜细胞凋亡数低于C组(P<0.05)。结论NEC新生鼠肠黏膜受损,增殖减慢,细胞凋亡数增加;补充Gln和EGF可促进NEC新生鼠肠黏膜隐窝细胞的增殖,减少肠黏膜细胞的凋亡,加快肠黏膜修复。     

谷氨酰胺对新生鼠坏死性小肠结肠炎的影响

目的探讨谷氨酰胺(glutamine,Gln)对新生鼠坏死性小肠结肠炎(necrotizing enterocoli-tis,NEC)肠黏膜修复的影响。方法新生1日龄Wistar大鼠30只随机分为三组,A组为正常对照组;B组为NEC模型组;C组为NEC模型后灌胃给Gln组(2·0g/kg·d)。建立NEC模型,连续3天给予新生鼠100%二氧化碳5min,然后再给予100%氧气5min,放回母鼠身边喂养,第4天断头处死新生鼠,取肠道组织待检。分别取近回盲段2~3cm肠道组织固定、包埋、切片。HE染色光镜下作病理学检查,应用免疫组化技术检测肠黏膜增殖细胞核抗原(PCNA)表达情况,原位末端标记(TUNEL)法检测肠黏膜细胞凋亡的变化。结果B组HE染色切片见肠壁有不同程度的损伤,病理评分的中位积分为3分;C组有的肠黏膜正常,有的轻度肠上皮细胞脱落,有的绒毛轻度坏死,病理评分的中位积分为1分。B组PCNA数量均低于A组及C组(P<0·01)。B组的肠黏膜细胞凋亡的数量高于A组及C组(P<0·01)。结论NEC时,新生鼠肠黏膜受损,增殖减慢,细胞凋亡的数量增加;补充Gln可促进NEC新生鼠肠黏膜隐窝细胞增殖,减少肠黏膜细胞凋亡数量,使肠黏膜修复加快。     

幼年大鼠内毒素血症时小肠上皮细胞凋亡及Caspase-3的表达

目的：儿科危重症中胃肠功能障碍的常见病因是严重感染,其发病机制与内毒素血症导致肠黏膜屏障功能破坏密切相关。该研究探讨幼年大鼠内毒素血症时肠黏膜屏障损伤的细胞凋亡情况及其可能的信号转导通路,为寻求新的治疗途径提供依据。方法：40只18日龄Wstar大鼠腹腔注射4mg/kg内毒素(大肠杆菌O55∶B5脂多糖1mg/mL)制成内毒素血症模型,对照组大鼠(n=40)腹腔注射1mL/kg生理盐水。两组分别在注射后2, 4, 6, 24, 72h处死8只大鼠,取4cm远端回肠,行苏木精伊红染色,光镜下观察小肠绒毛的病理变化,原位末端标记法(TUNEL)检测小肠上皮的细胞凋亡,免疫组织化学测定Caspase 3的表达。结果：光镜下对照组各时点小肠绒毛结构正常,内毒素组注射后4 ~ 72h可见少量炎症细胞浸润。注内毒素后2h上皮细胞凋亡和Caspase 3的表达明显增加,分别于24h和6h达高峰, 72h开始下降。内毒素组各时间点小肠绒毛上皮细胞凋亡指数和Caspase 3的表达均明显高于对照组,差异有显著性意义(P<0.01或P<0. 001)。结论：幼年大鼠内毒素血症时小肠上皮细胞凋亡增加,Caspase 3表达是其信号转导途径之一。细胞凋亡可能是严重感染时肠黏膜屏障破坏机制。     

不同剂量四氢叶酸钙对大剂量甲氨蝶呤化疗大鼠肠黏膜的保护作用

目的 探讨不同剂量四氧叶酸钙(CF)对大剂量甲氨蝶呤(HD-MTX)化疗大鼠肠黏膜的保护作用.方法 6 周龄Wistar大鼠60只随机分为5组,每组12只.A组:正常对照组,腹腔注射9 g/L盐水;B组:1?解救组(即CF解救剂量为MTX总量的1%,下同);C组:2?解救组;D组:8% CF解救组;E组:空白对照组,不予CF解救.B～E组均腹腔注射MTX(120 mg/kg),B～D组于腹腔注射MTX 12 h后肌注CF解救,1次/6 h,共7次.于最后一次肌注CF 18 h后杀死大鼠,取其空肠标本观察形态,切片观察测定绒毛长度隐窝深度.结果 A组肠壁厚弹性好,绒毛密集、排列整齐;B～E组肠壁充血水肿变薄,小肠绒毛变短,隐窝深度变浅.E组最重,B组次之.B～E组与A组比较有统计学差异(Pa＜0.05);C、D与B、E组比较有统计学差异(Pa＜0.05);C、D组比较无统计学差异(P＞0.05).结论 MTX可致大鼠黏膜损害,CF解救可减轻其黏膜损害,过度降低CF解救剂量达不到解救目的.     

葡聚糖硫酸钠诱导炎症性肠病大鼠结肠黏膜紧密连接蛋白表达及其通透性的改变

目的：建立葡聚糖硫酸钠（DSS）诱导的大鼠炎症性肠病（IBD）模型,观察其肠上皮紧密连接蛋白表达以及结肠黏膜通透性的变化。方法：将雄性Sprague-Dawley（SD）大鼠随机分为对照组和IBD模型组,每组27只,通过使用3% DSS持续经饮水途径饲养大鼠6 d后恢复正常饮水14 d建立IBD模型,对照组自由饮水。分别于DSS处理后第7天、第14天和第21天观察结肠黏膜病理变化,第21天取结肠组织标本检测髓过氧化物酶活性;采用Ussing chamber检测结肠上皮通透性;通过real-time PCR和Western blot从转录水平和翻译水平分析肠上皮紧密连接蛋白表达。结果：IBD模型组大鼠出现腹泻、便血、体重下降,炎症集中在远端结肠,表现为隐窝脓肿,炎症细胞浸润。与对照组比较,IBD模型组大鼠结肠髓过氧化物酶活性显著增加（P<0.01）,肠上皮跨膜电阻抗值和跨膜电势差显著降低（P<0.01）,短路电流值明显增加（P<0.01）;Real-time PCR和Western blot的结果均提示正常大鼠尚未检测出claudin2的表达,IBD模型组 claudin2 mRNA及蛋白表达阳性;IBD模型组 occludin、claudin3、ZO-1 mRNA及蛋白表达水平均显著低于对照组（P<0.01）。结论：IBD大鼠结肠黏膜屏障功能受损,多种紧密蛋白表达改变,其中紧密连接蛋白表达变化可能在慢性修复期IBD屏障受损发病机制中起到重要作用。     

c-kit在肠神经节细胞发育过程中的作用

目的 初步探讨c-kit在肠神经节细胞发育中的作用.方法 体外培养大鼠肠神经节细胞及骨髓间充质干细胞(BMSCs),并在GDNF与胎肠培养基(FGCM)培养的条件下诱导BMSCs分化为肠神经节细胞.免疫组织化学方法 鉴定原代培养的肠神经节细胞神经丝蛋白(neurofilament,NF)的表达,用血管活性肽(vasoactive intestinal peptide,VIP)及NF鉴定BMSCs诱导分化的肠神经节细胞.RT-PCR分别检测原代肠神经节细胞、BMSCs以及诱导之肠神经节细胞的c-kit的表达.结果免疫组化结果显示纯化后的肠神经节细胞表达NF,流式细胞学检测第四代后的BMSCs高表达CD90,而不表达CD45,诱导后的肠神经节细胞可表达VIP及NF,而其余两组则不表达.RT-PCR结果示原代肠神经节细胞及BMSCs不表达c-kit,诱导后的肠神经节细胞可表达c-kit.结论 在体外能成功培养大鼠肠神经节细胞及BMSCs并纯化,BMSCs可被诱导为肠神经节细胞并表达肠神经递质.在肠神经系统的发育过程中,c-kit可能在某一阶段起到一定作用,在肠神经细胞逐渐发育成熟时接受到某些信号而关闭.     

白藜芦醇对大鼠肠缺血再灌注致肠黏膜通透性改变的影响

目的 探讨白藜芦醇(RES)对肠缺血再灌注致肠黏膜损伤大鼠的保护作用及其可能机制.方法 成年雄性SD大鼠24只随机分为假手术组、缺血再灌注损伤组、RES治疗组.假手术组仅分离肠系膜上动脉(SMA)而根部不夹闭.肠缺血再灌注损伤组和RES治疗组均用无损伤血管夹夹闭SMA根部,分别立即经阴茎背静脉注射9g·L-1盐水、RES( 20 mg·kg-1),45 min后放松血管夹形成再灌注.各组大鼠均于制模后6h采集静脉血和回肠标本.检测血清二胺氧化酶(DAO)及小肠脂肪酸结合蛋白(IFABP)水平,应用原位末端转移酶标记法检测肠黏膜上皮细胞凋亡率,HE染色法观察肠组织病理损伤情况.结果 肠缺血再灌注6h后,RES治疗组DAO及IFABP水平与肠缺血再灌注损伤组比较显著减少[DAO:(1 650±1 150)U·L-1vs(2920±1 520)U·L-1;IFABP:(845.12±123.86) μg·L-1vs(1 443.76±174.62) μg·L-1,Pa＜0.05],但二组较假手术组[(630±150)U·L-1,(26.76±4.86)μg·L-1)]均显著增加(Pa＜0.05).假手术组大鼠肠绒毛顶部、固有层和黏膜下层只有少量散在分布的凋亡细胞,缺血再灌注损伤组大鼠肠黏膜凋亡阳性细胞数量较假手术组明显增加[(66.63±1.71)％ vs (9.60±1.76)％,P＜0.05],分布范围从绒毛顶部扩大到中、底部,固有层和黏膜下层,细胞凋亡亦明显加重;RES组大鼠肠黏膜细胞凋亡率[(46.72±1.50)％]明显低于缺血再灌注损伤组(P＜0.05).结论 RES对肠缺血再灌注损伤具有保护作用,其机制可能与其抑制肠黏膜上皮细胞凋亡有关.     

谷氨酰胺对新生鼠坏死性小肠结肠炎的影响

目的 探讨谷氨酰胺(glutamine,Gln)对新生鼠坏死性小肠结肠炎(necrotizing enterocolitis,NEC)肠黏膜修复的影响.方法 新生1日龄Wistar大鼠30只随机分为三组,A组为正常对照组;B组为NEC模型组;C组为NEC模型后灌胃给Gln组(2.0 g/kg·d).建立NEC模型,连续3天给予新生鼠100%二氧化碳5 min,然后再给予100%氧气5 min,放回母鼠身边喂养,第4天断头处死新生鼠,取肠道组织待检.分别取近回盲段2～3 cm肠道组织固定、包埋、切片.HE染色光镜下作病理学检查,应用免疫组化技术检测肠黏膜增殖细胞核抗原(PCNA)表达情况,原位末端标记(TUNEL)法检测肠黏膜细胞凋亡的变化.结果 B组HE染色切片见肠壁有不同程度的损伤,病理评分的中位积分为3分;C组有的肠黏膜正常,有的轻度肠上皮细胞脱落,有的绒毛轻度坏死,病理评分的中位积分为1分.B组PCNA数量均低于A组及C组(P＜0.01).B组的肠黏膜细胞凋亡的数量高于A组及C组(P＜0.01).结论 NEC时,新生鼠肠黏膜受损,增殖减慢,细胞凋亡的数量增加;补充Gln可促进NEC新生鼠肠黏膜隐窝细胞增殖,减少肠黏膜细胞凋亡数量,使肠黏膜修复加快.     

Cellular adaptation of the rat small intestine after proximal enterectomy: changes in microvillous enzymes and in the secretory component of immunoglobulins

To investigate the adaptation of functions expressed by the villous and crypt cell of the intestinal mucosa after intestinal resection, a 50% proximal enterectomy or a single transection was performed in 16 growing rats weighing 175-200 g. Ten days following the enterectomy, we determined the mucosal mass parameters (weight, protein, and DNA content), the activity of microvillous enzymes (lactase, sucrase, and aminopeptidase) in villus cells, and the concentration of the secretory component of immunoglobulins in crypt cells isolated from the proximal intestinal remnant. Mucosal hyperplasia was attested by the finding that mucosal weight, protein, and DNA content per cm of intestinal length were significantly (p less than 0.01) higher (+29 to +48%) in the resected group than in transected controls. The specific activity of lactase, sucrase, and aminopeptidase were significantly (p less than 0.05) lower (-23 to -56%) in villous cells isolated from the intestinal remnant of resected rats compared to controls. Sucrase activity was depressed in each cell fraction of the entire villous-crypt unit resulting in a lower villous to crypt gradient of enzyme activity. Km for the enzyme determined in villous cells was similar in both groups but the Vmax was reduced proportionally to the enzyme activity in the resected group indicating less enzyme per cell. By contrast, the concentration of secretory component measured by an immunoradiometric assay in both villous and crypt cells was significantly (p less than 0.05) increased (+37 to 45%) following proximal enterectomy. Our data indicate that the response of the epithelial cell to intestinal resection varies according to the metabolic function and that the mechanism of adaptation at the cellular level is complex.     

Differential appearance of T cell subsets in the large and small intestine of neonatal mice

We examined the appearance of intestinal intraepithelial lymphocytes (IEL) during the first 12 wk of life to gain insight into postnatal factors that contribute to the differences found between IEL in the large and small intestines of adult mice. Intestinal T cells were very infrequent at birth, but increased in number in the large and small intestine during the first 4 wk of life and then stabilized. The small intestinal epithelium at 2 wk of age contained mostly T cell receptor (TCR) alphabeta+, CD2+ T cells, unlike IEL in adult mice, which were composed of nearly equal proportions of CD2-, TCR alphabeta+ and TCR gammadelta+ cells. Between 2 and 3 wk of age, TCR gammadelta+, CD2- IEL increased greatly in the small intestine, whereas TCR alphabeta+ cells expressing CD2 decreased. By contrast, IEL in the large intestine at 2 and 3 wk of age were mostly TCR alphabeta+, CD2+ T cells similar to large intestinal IEL in adult mice. And finally, the expression of CD69 increased earlier and to higher levels on TCR alphabeta+ and TCR gammadelta+ IEL in the small intestine than in the large intestine. Our results demonstrate that IEL in the large and small intestine are phenotypically similar during suckling and that differences between these populations are established after weaning. Furthermore, the earlier accumulation of IEL with an activated adult IEL phenotype in the small intestine suggests that these T cells mature or expand in the gut and contribute to the maturation of immune function during postnatal life in mice.     

Adaptive response of growing rat small intestine to acute Adriamycin injury

The response of the intestinal mucosa to Adriamycin (ADR) was studied in the duodenum, jejunum, and ileum of 25-day-old rats. A single injection of ADR resulted in decreases in mucosal DNA per centimeter of length and in sucrase activity, which were proportional to the doses given (2, 5, and 8 mg/kg). ADR at 2 mg/kg had no significant effect on body weight, gut length, epithelial structure, or mucosal protein content per unit length. The morphological modifications occurred mostly in the proximal intestine and consisted of villous atrophy and degenerative changes of villus and crypt cells. A single dose of 5 mg ADR/kg acutely affected the gut. At 48 and 96 h the changes were characterized by marked decreases in mucosal weight, DNA per centimeter, sucrase activity, and villous shortening. At 144 h, the ADR-treated intestine entered a highly proliferative state and showed increased villous height, mucosal weight, and DNA per centimeter. Although villous hyperplasia was observed at 144 and 192 h, the mucosal weight and DNA concentrations did not exceed the corresponding levels in the control. During the period of active epithelial proliferation, sucrase activity remained depressed. We conclude that in the growing rat: (a) the acute intestinal injury of ADR is short-lived, dose dependent, and predominates in the proximal small intestine; (b) the enteric mucosa reacts to cytotoxic injury by excessive proliferation of immature enterocytes; and (c) the hyperplastic response to ADR is confined to the mucosal epithelium.     

A combination of dexamethasone and glucagon-like peptide-2 increase intestinal morphology and glucose uptake in suckling rats

OBJECTIVES: Glucagon-like peptide (GLP)-2 enhances nutrient uptake in adult animals. Glucocorticosteroids accelerate intestinal ontogeny and increase nutrient uptake in adult animals. We hypothesized that administering GLP-2 and dexamethasone (DEX) to suckling rats will enhance sugar uptake and that this effect persists into the postweaning period. METHODS: Suckling rats were treated for 10 days with GLP-2 (0.1 microg/g/d, twice daily), DEX (0.128 microg/g/d, once daily), GLP-2 + Dex (same doses as above), or placebo. The rate of intestinal uptake of glucose and fructose in sucklings (19-21 days old) and weanlings (49 days old) was assessed using an in vitro ring technique. RESULTS: DEX reduced body weight in weanlings, whereas GLP-2 + DEX prevented this effect. In sucklings, GLP-2 + DEX increased ileal villous height and jejunal and ileal villous width and crypt depth. In sucklings, GLP-2 + DEX increased the maximal transport rate (Vmax) for jejunal glucose uptake, whereas DEX reduced the ileal Vmax. In weanlings, GLP-2 + DEX increased jejunal villous height, whereas ileal villous width and crypt depth were reduced. DEX increased the ileal Vmax and apparent affinity constant for glucose in weanlings. CONCLUSIONS: The combination of these hormones may be useful in stimulating glucose uptake in the developing intestine, and giving DEX to sucklings may enhance glucose uptake in later life.     

Changes in upper intestinal epithelial morphology and kinetics in the growing guinea pig

Weaning, the process of intestinal adaptation from milk to solid diet, demands changes in gastrointestinal function. We aimed to measure upper intestinal mucosal morphology and cytokinetics during early life, to determine whether the marked changes seen at weaning in altricial species, such as rat and mouse also occur in the precocial guinea pig. A total of 79 animals was studied. Jejunal morphology was measured by microdissection and crypt cell production rate by a metaphase arrest technique in animals at 1, 7, 14, 21, and 28 days after birth. There was a 40% decline in villus height from 986 to 576 microns during the first 2 wk (p less than 0.001). Crypt depth increased by 25% from 148 to 199 microns (p less than 0.01). After an initial decline there was a significant increase in crypt:villus ratio from 6.7 to 8.2 (p less than 0.001), in crypt cell production rate from 3.9 to 5.6 cells/crypt/h (p less than 0.001), and net villus influx from 26.1 to 45.9 cells/villus/h (p less than 0.001) from 14 days onward. These proliferative changes were accounted for by an increase in the depth and number of crypts, and in crypt cell production rate, leading to an increase in net villus influx. In contrast with the rat and mouse they were gradual, occurred largely during the 3rd wk, and appeared to follow the cessation of breast feeding and commencement of solid food. It is suggested that the functional changes in the small intestine that occur during weaning in the guinea pig are neither due to rapid proliferation of a new epithelial cell population, nor precipitated by change in diet.     

Inositol phosphatase in developing rat duodenum, jejunum and ileum

Inositol phosphatase and phytase activities in different segments of the rat small intestine were measured during postnatal development. In the duodenum and jejunum, inositol phosphatase activity (units/g tissue) was low during the suckling period and increased at weaning, reaching a peak of activity at 4 weeks of age. In the ileum, peak activity was observed during the suckling period with a sharp decline at weaning. Phytase activity was very low during the suckling period in all segments, and increased to exhibit a peak at 4 weeks of age in the duodenum, and to a lesser extent in the jejunum (low activity was maintained in the ileum). The content of inositol phosphatase activity in the duodenum increased rapidly during the suckling period to reach its maximum at 4 weeks of age. This suggests a relationship to cell proliferation rate in the small intestinal mucosa.     

Effect of the lectin concanavalin A on the neonatal guinea pig gastrointestinal mucosa in vivo

The effect of intrapharyngeal infusion and subsequent passage of the lectin concanavalin A through the gastrointestinal tract of neonatal guinea pigs was examined. The lectin, administered at a concentration of 1 mg/ml, caused considerable mucosal damage in the stomach. Subsequent passage of the lectin through the small intestine caused little cellular damage to the mucosa, as judged by light and electron microscopy. Parallel morphometric analyses of the jejunum showed a decrease in mean villus height and an increase in mean crypt depth of 8% after 5 h of lectin administration. A 4.7-fold increase in jejunal crypt cell production rate was observed, accompanied by a statistically significant increase in the number of intraepithelial lymphocytes. These morphologic and kinetic changes were accompanied by a three-fold increase in the urinary lactulose:mannitol excretion ratio, indicative of a loss of mucosal integrity. No systemic antibody response to concanavalin A was demonstrated within 5 h of intragastric infusion of the lectin. Concanavalin A, conjugated with 10 nm colloidal gold particles, was also directly infused into the lumen of the jejunum in vivo. Within 60 min, both villous and crypt epithelial cells contained gold particles, demonstrating the rapid accessibility of crypt cells to the lectin. Intercellular spaces appeared within the villous epithelium, although both junctional complexes and spot desmosomes were retained. The brush border was abnormal with signs of incipient vesicularization. These findings have implications for our understanding of the pathogenesis of childhood coeliac disease and for the vulnerability of the neonatal gut to food proteins.     

Celiac disease: from inflammation to atrophy: a long-term follow-up study

OBJECTIVES: Celiac disease develops gradually from lymphocytosis, crypt hyperplasia and minor villous atrophy to overt villous atrophy. It IS NOT known how such minor mucosal changes predict eventual celiac disease. The aim of this study was to evaluate the role of intraepithelial lymphocytosis and marginally decreased villous height/crypt depth ratio in the development of overt villous atrophy in a long-term follow-up. METHODS: The authors evaluated 980 small bowel biopsies of children who had previously been studied and found to be histologically negative for celiac disease between 1976 and 1992. Villous height/crypt depth ratio and the number of intraepithelial lymphocytes were measured in these initial biopsies. Cases with slight biopsy changes were identified for further study and sex and age matched subjects with normal biopsies from same group were selected as controls. They all were asked to submit serum samples for gliadin, endomysial and tissue transglutaminase antibodies 8 to 28 years after the initial biopsy. Those with positive screening tests were asked to undergo endoscopy and small intestinal biopsy. RESULTS: 236 cases with slight changes were identified, and 236 with normal mucosa served as controls; 76 cases and 68 controls participated in the follow-up study. Ten individuals had positive screening test results. Two new celiac disease patients, one in each group, were found. Four patients in the case group had been diagnosed with celiac disease by routine procedures during the follow-up. Thus, five cases and one control had developed celiac disease. CONCLUSIONS: Small bowel mucosal lymphocytosis or slight reduction in villous height/crypt depth ratio are common findings in patients with suspicion of celiac disease. These findings alone are poor predictors of celiac disease.