April 1995 Growth, Development, and Nutrition A743

MARKED PAUCITY OF GASTROINTESTINAL. ENDOCRINE CELLS (GIECs) IN A CHILD WITH POLYGLANDULAR AUTOIMMUNE (PGA) SYNDROME, PERNICIOUS ANEMIA (PA), AND STEATORRHEA MM Oliva and JH Yardley. Depts of Pediatrics and Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD

The polyglandular autoimmune (PGA) syndromes are characterized by the dysfunction of two or more endocrine organs due to autoimmune mechanisms' (Ped Annals 9:154, 1980). A subset of patients have associated chronic steatorrhea which is often difficult to control. Previous explanations for this steatorrhea have included a direct effect of hypoparathyroidism and hypocalcemia, intestinal candidiasis, mucosal atrophy, pancreatic insufficiency and bile salt deficiency, yet, the specific pathophysiological mechanism(s) remain unknown. Here, we present gastrointestinal (GI) findings in a 12 year-old female with hypoparathyroidiSrn, PA with positive antibodies to intrinsic factor, steatorrhea, hypothyroidism, mucocutaneous candidiasis, and ovar!an failure. An extensive work-up done at an earlier age looking for an etiology of the steatorrhea had not yielded significant results. To further evaluate her GI tract, the patient underwent an upper endoscopy and flexible sigmoidoscopy. Biopsies were obtained from the esophagus, gastric antrum and body, duodenal bulb and second portion, and rectosigmoid. RESULTS: The patient's antral and corporal mucosa showed autoimmune-type atrophic gastritis with no oxyntic glands or parietal cells being seen. However, instead of the hyperplasia of GIECs that usually accompanies PA, the gastric mucosa was devoid everywhere Of GIECs by argyr0philia (Grimelius), and in immunostains for chromogranin and for gastrin. In keeping with these findings, serum gastrin levels were in the low normal range (22-35 pg/ml) whereas high circulating gastrin, often exceeding 1000 pg/rnl, is typical for PA. Furthermore, no GiECs could be demonstrated in duodenal mucosa taken currently and when the patient was 3 years-old (1 year after onset of the steatorrhea). Finally, only rare argyrophilic and chromogranin positive GIECs were identified in sigmoidal and rectal mucosa. CONCLUSIONS: Paucity of GIECs has not been previously reported in PGA syndromes. Although we cannot exclude a congenital hypoplasia of the GIEC system in this patient, these findings suggest that GIECs can be included in the generalized destruction of endocrine organs. Paucity of GIECs may be an important factor in PGA syndrome-associated steatorrhea; however, this needs further investigation.

LOWER ESOPHAGEAL SPHINCTER FuNcTION IN PREMATURE INFANTS T Or0eri, G Davidson, K Miki, R Haslam, W GoJdsworthy, M Bakewell, R Fraser, J Dent. Depts Neonatology, Gastroenterology and Biomedical Engineering, Womens and Childrens Hospital and Gastrointestinal Medicine, Royal Adelaide Hospital, Adelaide, Australia,

Gastro-esophageal reflux disease is an important cause of morbidity in premature infants, but the motor mechanisms responsible for reflux are unknown. In 42 healthy preterm neonates (postconceptional age (PCA) 33-38 weeks), a miniaturized multilumen catheter (OD 2.0ram) incorporating a lower esophageal sphincter (LES) sleeve was passed transnasally in place of a standard 5Fr gavage tube. This previously validated technique (Gastroenterology. 1994; 107(4):

247) enables high-fidelity recording of pharyngeal, esophageal, LES and gastric pressures at a perfusion rate of 0.05 ml/min. Standard liquid feeds were administered via the manometric assembly. LES pressure (LESP) was recorded in 32 infants for 15 min immediately before and after feeding. In a further 10 infants oesophageal body and LOS pressures were recorded for 2 hours following the feed.

In all infants a high pressure zone was present at the LES and swallowing induced esophageal body contraction and LES relaxation. Mean LESPs(+SEM) were higher preprandially than postprandially (20.5_+1.7 v 13.6_+1.3 mmHg, p<0.0005). Preprandial but not postprandial LESP increased with increasing PCA (see table, *p<0.05 cf preprandial pressures using paired t-test). The mechanics of swallow-related LES relaxation were investigated by examining 202 swallow sequences during which a distinct LES relaxation occured within _+S sec of a single pharyngeal contraction. 94% of these swallows triggered esophageal body peristalsis. In 83% of cases, the onset of LES relaxation oecured between 1 sec before and 3 sec after the upstroke of pharyngeal contraction (mean _+SEM = 0.70_+0.11 sec). The duration of LES relaxation, time from onset until LESP returned to pre-swallow pressure, ranged from 4 to 18 sec with a mean of 9.5_+0.2 5ec. All infants demonstrated transient LES relaxations. In 8 of 10 studies these resulted in esophageal body common cavity episodes, indicating reverse flow into the esophagus.

Preprandial Postprandial PCA (wks) LESP (mmHg) LESP (mmHg) 33-34 (n=l 3) 16.6_+1.6 12.9-+2.3 35-36 (n=72) 22.5_+2.6 14.9+2.0" 37-38 (n=7) 25.7-+5.1 13.5+2.1"

Our data indicate that LES tone and relaxation mechanisms are well developed by 33 weeks PCA. Transient relaxation of the LES may be one mechanism for gastro-esophageal reflux in premature babies.

O AGE DIFFERENCES IN TEl (IL-2/IFN-7) AND TM2 (IL-4/IL-10) CYTOKINE PRODUCTION BY MURINE SPLEEN (SpN) AND MESENTERIC LYMPH NODE (MLN) T CELLS AND CD4 T SUBSET CELLS. E.K. Onuma and H. Kawanishi, UMDNJ-Robert Wood Johnson Medical School/ New Brunswick, NJ.

The effect of aging on T cell cytokine production was studied in vitro. SPN and MLN T cells and CD4 T subset cells were separated from young (2-3 months old} and aged (23-24 months old) Balb/c mice. After optimal stimulation with phorbol myristate acetate (10ng/ml) and ionomycin (10Ong/ml), the supernatants were collected at O, 12,24,48,72, and 96 hrs. Quantitation of IL-2, IL-4, IL-10, and IFN- 7 was determined by ELISA. This reflected net cytokine production.

RESULTS: The SPN and MLN T cells from both the young and aged mice showed a significant net production of IL-2. At 96 hrs, SPN and MLN IL-2 concentrations were 9,145 pg/ml and 10,000 pg/ml, respectively, in the young mice, and 5,865 pg/ml and 7,308 pg/ml, respectively, in the aged mice. In the aged mice, the CD4 T subset cells also showed a significant net production of IL-2 (at 96 hrs, 6,601 pg/ml in SPN and 12,096 pg/ml in MLN). However, in the young mice the SPN CD4 T subset cells showed only minimal net production of IL-2 (1,062 pg/ml at 96 hrs) and the MLN CD4 T subset cells showed no significant net production.

Net production of IFN- 7 was significant in SPN T cells from young (339 pg/ml at 96 hrs) and aged (423 pg/ml at 96 hrs) mice, and minimal in SPN CD4 T subset cells from young (peak at 72 hre at 125 pg/ml) aod aged (162 pg/ml at 96 hrs) mice. There was no significant net production of IFN- 7 in MLN T cells and CD4 T subset cells from both age mice. There was no significant net production of IL-4 in T cells and CD4 T subset cells from SPN or MLN from young mice. Aged SPN T cells and CD4 T subset cells showed a significant net production (562 pg/ml and 470 pg/ml, respectively, at 96 hrs) as did aged MLN T cells and CD4 T subset cells (293 pg/ml and 417 pg/ml, respectively, at 96 hrs). No significant net production of IL-IO was found in SPN and MLN T cells and CD4 T subset cells from young mice. Aged SPN T cells and CB4 T subset cells showed a significant net production (582 pg/ml and 545 pg/ml, respectively, at 96 hrs), but aged MLN T cells and CD4 T subset cells showed no significant net production of IL-10.

CONCLUSIONS: I) The production of IL-2 in young SPN and MLN T cells is greater. The minimal and insignificant net production of IL-2 by young SPN and MLN CD4 T subset cells, respectively, could be explained by augmented consumption by the activated CD4 T subset cells from young mice. 2 l SPN cells from young mice showed a THI response, but those from aged mice showed both TNI and TH2 responses. 3) No consistent correlation of TNI and TH2 cytokine net production was observed in MLN cells of both age groups.

EFFECTS o F DIETARY FAT REDUCTION AND L-GLUTAMINE SUPPLEMENTATION ON WEIGHT GAIN. E.C. Onar~,, A. Petro, A. Tevrizian, M.N Feinglos, R.S.Surwit. Departments of Surgery, Medicine and Psychiatry, Duke University Medical Center, Durham, NC

We previously showed that when two strains of mice were fed a high-fat (58%), low-sucrose (HL) diet, it caused excessive body weight (BW) gain in the C57BL/6J (B6/J) but not the A/J, suggesting a genetic predisposition to development of obesity in the B6/J during high-fat feeding. Although there is a growing interest in the metabolic effects of L-glutamine (GLN), a preferred fuel for the gastrointestinal tract, the role played by this amino acid in energy balance is not clear. The AIM of the present study therefore, was to examine the effect of dietary GLN supplementation on BW during high-fat feeding and to compare it with dietary fat reduction. MF3,ROD: Each group of ten B6/J mice was fed one of four diets: low-fat (10,5 %), low- sucrose (LL), HL(58%), HL(45 %) alone or with GLN (2.7%) for four months. BW and food intake were determined routinely and fecal fat output was measured in samples collected over 3 days at the end of this period. lh~SI2LT~: No difference in food intake between any diets was observed at any given time. Also, reduction of dietary fat from 58% to 45% did not cause a statistically significant change in the mean ___ SEM, BW (42.5 + 1.3 vs~39.7 5:1.9 g, respectively), at month 4. However, the animals on GLN supplementation in the HL (45%) showed a 10% reduction (p < 0.05), in BW by month 2, compared to those on the same diet without GLN. The BWs of the animals fed the LL and HL(45%) + Gin were 26.9 + 0.7 and 33.1 + 1.1 g, respectively (p < 0.01), at month 4. Percent fecal fat output was similar between HL (45%) without (6.1 :k .008) and with GLN (5.98+ .007), showing that GLN-mediated reduction in BW was not due to fat malabsorption. The food conversion efficiency defined as weight gained/calories consumed x 100, obtained during HL (45%) + GLN was not different from that of LL group (11.43 ___ 0.9 vs 10.17 -I- 0.88 %, respectively) compared to 14.56 + 1.42 for HL (45%) alone. . C , ~ : Whereas reduction of dietary fat from 58% to 45% did not affect the development of obesity, supplementation of high fat diet with GLN caused a reduction of weight gain in B6/J mice, suggesting the possible use of GLN as an antiobesity nutrient.