At222 SSAT ABSTRACTS GASTROENTEROLOGY, VoI. IO8, No. 4

• METASTATIC AND NON-METASTATIC COLORECTAL CANCER CELLS (CRC) INDUCE HOST METALLOPROTEINASE PRODUCTION in vivo. J.G. Guillem, M.P. Murray, Z.S. Zenq, C.J. Swallow, and M. Kuranamt. Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York.

Complex regulation of metalloproteinase (MMP) activity in the tumor mieroenvironment defines the extent of extracellular matrix degradation and facilitates invasion and metastasis. We have previously demonstrated that the principal basement membrane degrading MMPs (MMP-2 and MMP-9) are stromal in origin, suggesting that host stromal cell MMP production may be induced by contiguous CRC cells, AIM: To determine in vivo if metastatic and non-metastatic human CRO cells can induce host (mouse) MMP-2 and MMP-9 production. METHODS: Clones of increasing metastatic potential ($1-$5) were generated from the non-metastatic human CRC tins, SW620-P by serial cecal transplantations in BALB/c nude mice. For in vivo studies, 107 cells of each line were injected into the subcutaneous space of nude mice. Tumors were grown to 1 cm diameter, excised and homogenized for analysis. MMP activity and mRNA expression were determined by gelatinase zymography and Northern blot analysis, respectively. Experiments were done in triplicate. RESULTS: Neither the parental line nor the $1-$5 SW620 clones expressed MMP-2 or MMP-9 mRNA in vitro. Furthermore, no MMP activity was detected in either conditioned medium nor cellular extracts from any of these CRC lines. TPA, a known tumor promoter and enhancer of MMP production failed to induce MMP mRNA expression in any of the CRC lines studied, confirming the inability of the CRC cells to express MMP, even with exogenous stimulation (100 ng/ml TPA). In contrast to these in vitro findings, subcutaneous CRC tumors generated in vivo from both the SW620- P line and the S1-SS clones were positive for both MMP-2 and MMP-9 gelatinase activity. MMP-specific activity was verified by complete inhibition by EDTA, an MMP inhibitor. The presence of MMP-2 and MMP-9 protein in the CRC tumors formed in vivo was further confirmed by Western blotting with monoclonal antibodies. Significantly all of the subcutaneous tumors lacked MMP-2 and MMP-9 mRNA expression, as determined using hurrrr~n specific cDNA probes. Taken together these data indicate a murine stromal cell source for MMP production ~ vivo. CONCLUSION: CRC cells do not themselves produce MMP-2 and MMP-9 but rather induce their production by host cells. Comparable in vivq induction of host MMP activity by non- metastatic and metastatic CRC cells is consistent with the notion that numerous properties, in addition to increased local invasion, define the metastatic phenotype.

DIRECT INHIBITORY ACTION OF ERYTHROMYCIN ON THE GALLBLADDER MUSCLES. M. Hanani A.

Y. Mashri.ki. ~ Zh~_.ha_Ag= ~-'. ~ n.~_~ ~ . Haoassan unwers~ty Nos.PLtal ano

Hebrew university-Hadassah Medical School, Jerusalem 91240 Israel. In vivo stud es on humans and anima s showed that e r y t h r o m y c i n ( E M ) increases gal lbladder empty ing in. an unknown mechan ism, W e measured the act ions of EM on isolated gallbladders from guinea-pigs and humans, using isometric force measurements. _ ~ , _ ~ : Electrical st imulat ion of whole guinea-pig.gal lbladders evoked contr.actions that were medmted .by ace- tylcholine release. EM (1 raM) reduced these re sponses by 43% ( p < 0 . 0 5 N = 4 ) . Carbachol (a muscar!nic cholinergic agonist) caused contrac- tions that were diminished b y E M in a dose- dependent manner: at 200 /JM by 12%, at 500 _pM by 3 3 % and .at 1 mM by 5 7 % ( P < 0 . 0 5 , N = 10). These results suggested that EM blocked choline_rgic responses In an atropine-like mecha- nism. Io test this possibility we measured con- tractions of guinea-pig gallbladders in response to the a a.drenergic agomst phenylephrine. EM antag- onized the resp_onses to phenylephrine dose- del~endently: at 50 pM we measured a reduction of 20%, at 200 p M a reduction of 38%, and at 5 0 0 / I M , 79% (p<O.05, N = 5 ) . Thus the actions of EM appeared not to be due to muscarinic an tagomsm but v ia a more genera l i zed , s t i l l u,nk,nown inhib i tory mechanism. I.n isola_ted .gaJL- maaaers trom. pat ients we Tound that hM (,50O pM) reduced the responses to electrical stimula- tion by 29 + 6% ( N = 9 , 4 patients), and to carbachol by 48 + 5% ( N = 1 8 , 5 pat ients); C onclusions. Thedirect effect of EM on soatea guinea-pig and human gallbladders is inhibitory; in contrast to in vivo measurements where this drug enhanced gallbladder emptying.

• BUDD CHIARI SYNDROME: TREATMENT WITH P O R T A S Y S T E M I C SHUNT (PSS) OR LIVER TRANSPLANTATION (LT), A.W. Hemming. B. Langer. P.D.Grei=. B.R. Taylor. R. Adams. EJ. Heatheote The Toronto Hospital, Toronto, Canada.

Thirty patients with Budd Chiari syndrome seen at our institution between 1968 and 1994 were reviewed. The underlying etiology of the syndrome was related to oral contraceptives or identifiable coagulation disorders in 60% of cases, tumor in 10% and was idiopathic in 30% of cases. Preoperative liver biopsies showed centrilohular congestion and necrosis in all 19 patients who underwent portasystemic shunting and the presence of advanced cirrhosis in all six patients undergoing LT. Six of the patients had cirrhosis on biopsy but retained good hepatic synthetic function and underwent PSS. Three patients initially underwent PSS and subsequently required LT. Five patients underwent no operation either because of tumor unresectability or because of mortality prior to operation. Statistical analysis of outcome of those treated surgically included student t tests, Fishers exact test and Kaplan Meier survival analysis. Operative mortality in the PSS patients was 26 % although 2 of these 5 deaths arose in the pre-LT era in patients that would presently undergo transplant. There was no operative mortality in the LT patients. PSS patency at one year was 78%. Of the 6 patients undergoing PSS with cirrhosis 66% had patent shunts at i year which was not significantly different from the non cirrhotics.(p=0.37) Patients that were shunted with high caval gradients across the liver (> 12mm hg) but no caval thrombosis or web showed no difference in shunt patency as compared to PSS patients with low gradients(p=0.27). Overall 5 year survival was 65%. No advantage of PSS vs LT could be clearly demonstrated. Both PSS and LT arc options in the management of Budd Chiari syndrome, however they have different indications for use. PSS seems a reasonable initial approach even when there is cirrhosis if hepatic synthetic function is preserved. High caval gradients do not preclude PSS as long as there is no caval web or thrombosis. LT should be used in patients with poor hepatic synthetic function, end stage liver disease or vena caval obstruction.

THE BIOFRAGMENTABLE A/NASTOMOTIC RING (BAR) IS ASSOCIATED WITH POOR RECOVERY OF MOTILITY IN THE CANINE SMALL BOWEL. MP Hockinq, GV Scott, KI Bland, Departments of Surgery and Pathology, University of Florida College of Medicine and VAMC, Gainesville, FL. The BAR is being used increasingly in clinical practice. Previously we demonstrated that recovery of small bowel motility is better following an end-to-end (EE) than a functional end-to-end (FEE) anastomoses. The purpose of this study was to evaluate motility following small bowel anastomosis created with the BAR in a canine model. Five dogs underwent placement of electrodes at i0 cm intervals, beginning 5 cm distal to the pylorus. The duodenum was divided 30 cm from the pylorus with reanastomosis using a 25 x 1.5 mm BAR. Migrating myoelectric complex (MMC) propagation was determined out to 79 weeks postop. At study completion a stenosis index was calculated and the anastomoses were scored in a blinded fashion for fibrosis and alignment of the muscularis propria. RESULTS: All animals recovered uneventfully although two dogs died in the late postop period. By 1 yr postop only 26±8% of MMC's crossed the anastomoses, compared to our previous study in which 95±3% of MMC's crossed a hand-sewn EE and 59±7% propagated across an FEE anastomosis 1 yr postop (p<0.01 by ANOVA). Two animals (40%) developed a stricture at the BAR anastomosis~ Histologic evaluation demonstrated poor alignment of the bowel wall across the anastomoses. CONCLUSION: In a canine model, small bowel anastomosis with the BAR is associated with strictures and poor recovery of motility, apparently related to poor alignment of the bowel wall, suggesting that recovery of motility may be related not only to configuration but also to surgical technique.