A 7 4 6 A G A A B S T R A C T S G A S T R O E N T E R O L O G Y , Vol . 1 0 8 , No. 4

~Z]DENTZFZCATZONOF BONE NORPHOGENETZC pROTEIN (~-6) IN 8MOOTE I ~ S C L I DURING ~ INTESTINAL ORGANOGIU~]~SZ$. H.A. P e r t . S.E.Gitelman. Dept. of Pediatrics, University of California, San Francisco, CA

We previouslyreported effects of TGF-~I on intestinal smooth muscle cell proliferation and collagen synthesis during human fetal development. Another member of the TGF-~ auperfamily involved in embryonic induction is BMP-6. Studies in fetal mice implicate\BMP-6 in the development of epithelial, endochondral and neural tissues: a related peptide is crucial to gut morphogenesis in Drosophila. The current study examines the role of BMP-6 in human intestinal organogenesis. Poly- clonal antibodies to precursor and mature fragments of BMP-6 were used in immunohistochemical studies ofh~man fetal intestine at 15, 19, and 24 weeks gestation. 0nly the precursor protein displayed irmuunoreactivity. Staining was confined to muscle throughout the muscularis propria, muscularis mucosa and vasculature, its intensity increasing with a~e. Intestinal smooth muscle cells from 13 to 20 week fetuse~were lsolated, cultured in 10% fetal calf serum, pas- saged once~ and grown to confluence.BMP-6 n%RNA was detected by Northernblot analysis, quantitated by densitometry and normalizedto GADPH expression~!BMP-6 nd~NA abundance in intestinalsmooth muscle cells, increased 33% from 13 to 22 week s gestation.

Fetal *~:Je (wks) 13 17 22 mRl~& (O.D.) 2542.23 2916.00 3380.95

This iS the first study to demonstrate that BMP-6 is expressed during the development of t~e, human fetal intestine, but only in muscle. Expression increases with gestatlonal age as shown by abundance of mRNAs and intensity of in~nunohistochemical staining for the precursor fragment. Inability to detect the mature fragment with antibody~mey reflect inaccessibility due to tissue specifie'conformational differences, rapid degradation or binding to matrixJ Enhanced expression of BMP-6 coincides with muscle differentiation, the appearance of the museularis mucosacdecreased synthesisof TGF-~, and a decline in collagen aynthesis [described previ0usly:]. Exclusive expression 6~BMP-6 in muscle suggests a crucial role in human gut development that needs to be understood in the spatial and temporal context of associated TGF-~ superfamily members. NIH grant AR0189~ and Tooley Foundation Award-

• IGF-I ATTENUATES TPN:INDUCED CHANGES IN JEJUNAL STRUCTURE AND TRANSPORT FUNCTION. C.A. Peterson, D. M. Ney and H.V. Carev. Depts. of Nutritional Sciences and Comparative Bioscienees, University of Wisconsin, Madison, WI 53706

Maintenance of animals with total parenteral nutrition (TPN) leads to small intestinal muc0sal atrophy and reductions in several brush border enzymes. Few studies have examined whether TPN directly alters intestinal ion transport. Thus, the first aim of this study was to determine whether TPN affects basal and stimulated ion transport and ionic permeability of jejunal tissues in rats. A second aim of the study was to test the hypothesis that coinfusion of recombinant human insulin-like growth factor-I (rhlGF-I) with TPN solution would prevent TPN-induced changes in intestinal structure and function. Rats were fed ad libitum a semi-purified diet, given surgery, and then maintained with either TPN alone or TPN + rhlGF-I (800 #g/day) for 5 days. Results were compared with nonsurgical control animals (CON) fed the oral diet, On day 6, body masses 0fTPN and TPN/IGF-I groups were significantly less than in CON rats, and body masses of TPN/IGF-I rats were greater than inTPN rats. Jejunal mucosal mass and villus heights were similar in TPN/IGF-I and CON rats, and both were significantly greater than in TPN rats. Tissue conduetanees of jejunal tissues mounted in Ussing chambers were greater in TPN (45 + 4 mS/cm 2, n=l 1 tissues from 2 rats) compared with CON (19 _+ 1 mS/em 2 , n=19 tissues from 5 rats, P < 0201), but values in TPN/IGF-I rats were intermediate between the two (28 ± 2 mS/cm 2, n=36 tissues from7 rats, P < 0.001 from CON and TPN). Basal short-circuit currents (Isc, a measure of active ion transport) were 2-fold greater in TPN compared with CON or TPN/IGF-I rats. Maximal changes in Isc evoked by the CI- secretagogue earbaehol were greater in TPN rats (50 + 10 FA/cm ~ ) than in CON rats (8 + 2 #A/cm 2, P < 0.001), or in TPN/IGF-I rats (21 + 4 /zA/cm 2, P < 0.01); responses .in CON and TPN/IGF-I: rats were not significantly different. Decreases in Isc induced by norepinephrine (10 izM), which reflects NaCI absorption, were greatest in TPN rats and similar in CON and TPN/IGF-I groups. The absorptive response to mueosal addition of D- glucose was also significantly greater in TPN tissues compared with c o n Or TPN/IGF-I tissues. These results suggest that the absence of luminal nutrients during TPN reduces mucosal mass, increases ionic permeability and enhances ion transport responses to secretory and absorptive agents. Coinfusion Of rhlGF-I with TPN solution attenuates the functional changes induced by TPN; thus, IGF-1 has important therapeutic potential to maintain normal intestinal structure and function during TPN. Supported by NIH grant R29-DK42835.

EXPRESSION OF EPIDERMAL GROWTH FACTOR RECEPTOR (EGFr) ON GASTRICA MUCOSA AND RELATION WITH GASTRIC LESIONS AND INTESTINAL METAPLASIA., It Pe~ino, A. Di

Napol~ G. Ce~no, S. Av~none, M. Mes~acr, R. PuKlan6, *A. Ponzetto, L. Chianduasi. School o f Internal Me~ficine, S. Vito Hospital, University o f Turin, *Gastroenterology Department, S. Giovanni Hospital, Turin.

EGFr is ovcrexpresscd in gastric carcinom~ In our previous observations we reported that in about 20% of gastric ulcers there is a

overexpressio n o f EGFr. This study was designed to evaluate the EGFr data in relations to the various histological gaslric lesions and in particular to in tcs th~ mctaplasia, atrophy and folligular gaslrilis. I n this preliminary report we h a w considered 90 c a s e s : 9 gastric polyps, 9 gastroentero-anastomosis in incvious resections, 11 gaswie ulcers, 44 hyperemie or erosive gaslropathy and 17 cases endoscopically normal. All the palients were submitted to upper endoscopy and to biopsies: 4 antnd in normal cases and gastropathy, multiple biopsies in the other cases. The microtomic Slides were stained with haematoxylin and cosin for routine histology, while a slide for each case was incubated with the monoclonal anti EGFr clone F4 (for the internal domain) and processed for immunohistochcmis~'y with Biofin-Avidine complex. The results, revealed bY Diaminobcnzidine, were ¢valuamd in a scmiquanfimlive way at microscope. We observed 2 types o f positivity, l , more frequent, s t rom~ and 1 glandular. The results are reported in the following graph:

. POLYPS GASTROPATHY ULCERS GEA NORMAtS

IC)FolUcular 13Atrophic IIIntestlnalMet. DEGFrStroe,~ (3EGFrG,and. I

To conclude, in normal subjects we never found the positivity for EOFr in ~ n d s , which is strictly related to gastric lesions and to intestinal metaphsia. Stromal EGFr posilivity is related to gaslrilis. These data, ~hough preliminary, suggest further evaluations to establish their real si~iificance in gasWic lesions surveillance.

BIOCHEMICAl, MARKERS OF BONE TURNOVER IN PATIENTS ON HOME PARENTERAL NUTRITION (HPN): A FOLLOW UP STUDY. L.Pironi A.Maghetti, *C.Zolezzi, E.Ruggeri, E . I n c a s a * A . P i z z o f e r r a t o , L . B s r b a r a , M . M i g l i o l i . l s t i t u t o d i C l i n i c a M e d i c a e G a s h r o e n t e r o l o g i a , U n i v e r s i t ~ d i B o l o g n a ; * I s t . O r t o p e d i c i R i z z o l l , B o l o g n a , ITALY.

Eight pts on long-term HPN (4M, 4F; age 31-64 y r s ; C r o h n ' s w i t h s h o r t b o w e l , 3; s e l e r o d e r m a , 2; m e s e n t e r i c v a s c u l a r d i s e a s e a n d s h o r t b o w e l , 1; Rx e n t e r i t i s , 1: e n t e r i c f i s t u l a , 1 w e r e s t u d i e d a t 0 , 6 , 12 m o n t h s . The f o l l o w i n g w e r e e v a l u a t e d : s e r u m O s t e o c a l c i n l O S T = b o n e f o r m a t i o n m a r k e r } : u r i n a r y L y s y l P y r i d i n o l i n e (LP] a n d S - G a l a c t o s y l H y d r o x y l y s i n e (GHYL) t b o n e r e s o r p t i o n m a r k e r s } ; s e r u m PTH, C a l c i t o n i n , 2 5 v i t D , 1 - 2 5 v i t D ; s e r u m a n d u r i n a r y C a , Mg and P; b o d y w e i g h t ; r e h a b i l i t a t i o n d e g r e e [ I , a n c e t 2: 3 8 3 , 1 9 8 6 ] : HPN c h a r a c t e r i s t i c s I n u t r i e n t s a n d f l o w r a t e } . R e s u l t s : 3 p t s h a d : h i g h l e v e l s o f I,P a n d GHYL + n o r m a l l e v e l o f OST a t t i m e O; n o r m a l l e v e l s o f LP a n d GHYL ~ h i g h l e v e l o f OST a t ~ a n d 12 mos ; i n c r e a s i n g b o d y w e i g h t a n d r e h a b i l i t a t i o n d e g r e e b e t w e e n 0 and 12 mos . One p t had h i g h LP a n d GHYL + l o w OST l e v e l a t 0 , 6 a n d 12 mos a s s o c i a t e d w i t h d e c r e a s i n g b o d y w e i g h t a n d r e h a b i l i t a t i o n d e g r e e b e t w e e n 0 a n d ] 2 mos . F o u r p t s h a d s t a b l e b o n e t u r n o v e r , s t a b l e b o d y w e i g h t a n d r e h a b i l i t a t i o n d e g r e e d u r i n g t h e w h o l e f o l l o w u p : n o r m a l LP a n d GHYL - n o r m s ] OST, 1 p t ; n o r m a l LP a n d GHYL + low OST l e v e l , 2 p t s ; h i g h LP a n d GHYL l e v e l s ÷ n o r m a l OST, 1 p t . A s i g n i f i c a n t c o r r e l a t i o n w a s f o u n d b e t w e e n : LP a n d GHYL { 0 . 7 3 , p < 0 . 0 0 1 ) ; LP a n d 2 5 v J t D { - 0 . 6 4 , p < 0 . 0 1 l ; GHY[, a n d 2 5 v i t D { - 0 . 6 2 , p < 0 . 0 5 } ; OST a n d s e r u m Ca [ 0 . 5 5 , p<0.05). No correlation was found with the HPN characteristics. Conclusions: Bone turnover of pts or HPN: I) changes parallel to protein-calorie statue and physJea] activity: 2} in stable pt, s may show a l t e r a t i o n s o f o s t e o c l a s t i c o r o s t e o b l a s t i c a c t i v i t y ; 3) i s a s s o c i a t e d w i t h v i t D n u t r i t i o n a l s t a t u s .