ology

PI-38 Abstract id: 342.

L-glutamate secretion in the pancreatic juice involves transport andmetabolism of neutral amino acids in exocrine pancreas

Selene Araya 1, Christian Lutz 1, Evelyne Kuster 1, Luca Mariotta 1, BrigitteHerzog 1, François Verrey 1, Theresia Reding 2, Rolf Graf 2, SimoneCamargo 1.

1 Institute of Physiology and ZIHP, University of Zurich, Zurich,Switzerland2Department of Surgery, University Hospital Zurich, Zurich,Switzerland

Introduction: The pancreas efficiently absorbs amino acids (AA) forthe synthesis of enzymes, but also secrets free AA in the pancreatic juice.Under free protein diet (FPD), the AA release on the pancreatic juice (PJ)may play an important role on the homeostasis maintenance of the smallintestine.

Aims: The aim of this study was to analyze acinar synthase andsecretion of L-glutamate (Glu), the most concentrated AA in PJ.

Materials & methods: Expression of enzymes involved in Glu syn-thesis, AA concentration and ptotein localization were performed.

Results: Two glutaminase isoforms (gls1 and gls2) are expressed in thepancreas, and the mRNA levels of gls2 and of the alanine aminotransferase1 (gpt) were elevated in animals receiving (FPD). These results suggest Glumay be synthesized in the exocrine pancreas from L-glutamine (Gln) andL-alanine (Ala) and that the dietary protein content can modulate theexpression of enzymes involved in the synthesis of Glu. The secretorymechanism of Glu to PJ does not involve zymogen granules vesicles (ZGV).Glu and its precursors were not concentrated in ZGV but were found athigh concentrations in the cytoplasmic fraction, suggesting the secretorymechanism does not involve exocytosis. Immunofluorescence of pancre-atic tissue suggested that the Naao-dependent Glu transporter EAAT1(Slc1a3) localizes proximal to the apical membrane of acinar cells and maybe involved in the secretion of Glu.

Conclusion: These preliminary results suggest a new mechanism forGlu concentration and secretion on the PJ, as well a recycling of neutral AA(Ala, Gln) and Glu between the pancreas and intestine.

PI-39 Abstract id: 340.

Characterization of pericytes in adult pancreas tissue sections

Verena Barchfeld, Susanne Raulefs, Nadja M€aritz, Ivonne Regel, BoKong, J€org Kleeff, Christoph W. Michalski.

Department of Surgery, Klinikum rechts der Isar der TechnischenUniversit€at M€unchen, M€unchen, Germany

Introduction: Pericytes, the mural cells of blood vessels, are key reg-ulators of vascular morphogenesis and play a role in the developmentpancreas. Apart from their classical role in stabilizing vascular structures,the recent data suggest that a subset of pericytes have the properties ofmesenchymal stem or progenitor cells. The existence of such cells in adultpancreas has not yet been defined.

Aims: Several molecular markers for pericytes have been identified.However, the specific marker for pericytes remains unknown. The iden-tification of pericytes in tissue sections relies on the combination ofdifferent markers.

Materials & methods: To define the distribution of pericytes in theadult pancreas, we used the well established pericyte marker NG2 aloneand in combinationwith the endothelial marker CD31 or themesenchymalstem cell markers CD90, CD105 or CD146.

Results: Our data suggest an existence of a distinct cell pool within theadult pancreas which are double-positive for NG2 and mesenchymal stemcell markers. These data suggest that pericytes may have an additional roleother than stabilize the vessels.

Conclusion: These descriptive data argue for the heterogeneity ofpancreatic pericytes, whichmay play different roles in pancreatic physiology.

Abstracts / Pancreat

PI-40 Abstract id: 37.

Continuous regional arterial infusion of dextran 70 and heparin in thetreatment of severe acute pancreatitis: Background and design ofcohort interventional study

Mihailo Bezmarevic 1, Darko Mirkovic 1, Sinisa Rusovic 2, MiroslavMitrovic 1, Miodrag Mihajlovic 2, Milan Jovanovic 1, Milan Scepanovic 2.

1 Clinic for General Surgery, Military Medical Academy, Serbia2 Institute of Radiology, Military Medical Academy, Serbia

Introduction: Effects of continuous regional arterial infusion (CRAI)in acute pancreatitis (AP) treatment are reflected in increased tissueconcentrations of administered drugs. It was reported a lower mortalityrate in severe AP (SAP) when CRAI was applied within 72 hours of dis-ease onset. It is known that hyperosmolar solutions could reduceinterstitial and cellular edema, and shown that dextran can improvemicrocirculatory disorders in SAP. Coagulation disorders, endotheliallesions, vasospasm and the formation of microthrombi in pancreaticmicrocirculation reduce pancreatic perfusion which is well correlated tothe AP severity.

Aims: 0Materials & methods: Study will include all patients with APACHE II

score�10 calculated within the first 48 hours after AP onset. In the next 48hours, through micro-catheter placed in the celiac artery a CRAI of 500 mLof dextran 70with 5000 IU of heparin (CRAI-DH) will be infused in a rate of40mL/h, in addition to standard therapy. After catheter removal a standardtherapy will be continued. Intervention group will be compared with aretrospective control group of 30 patients with SAP treated without CRAI,in regard to the volume of pancreatic necrosis. A total sample size of 17patients was calculated to demonstrate that CRAI-DH combined withstandard therapy for AP can reduce the volume of pancreatic necrosis atleast 30% compared to the control group with 80% power at 5% alfa.

Results: 0Conclusion: This study is designed to reveal a reduction of pancreatic

necrosis by CRAI-DH combined with standard therapy in comparison withstandard therapy alone in patients with SAP.

PI-41 Abstract id: 269.

Mean platelet volume (MPV) as prognostic factor in acute pancreatitis(AP)

Neven Franji�c, Ivana Mikola�sevi�c, Davor �Stimac.

Division of Gastroenterology, Department of Internal Medicine,University Hospital Rijeka, Croatia

Introduction: Mean platelet volume (MPV) is a machine-calculatedmeasurement of the average size of platelets and is typically included inblood tests as part of the complete blood count. Vascular thrombosis andsystemic hypercoagulable states are well documented complications ofacute pancreatitis (AP). Higher values of MPV have been associated withthrombotic disorders. According to the literature, only few studies haveinvestigated the association between AP and MPV.

Aims: To determine whether the value of MPV at admission correlateswith the occurrence of local and systemic complications of AP; lethaloutcomes; and severe form of AP, according to modified Atlanta criteria.

Patients & methods: 53 patients (35 male and 18 female) wereenrolled in this retrospective study. MPV values were obtained on anautomated hematology analyzer (Olympus AU 640, Tokio, Japan). Student’st-test was used for statistical analysis.

Results: There were no statistically significant differences in theaverage values of MPV regarding local complications (7.51�0.99 vs.7.91�1.24, p¼0.22), systemic complications (7.60�1.05 vs. 7.72�1.22,p¼0.76), severe form of AP (7.47�0.97 vs. 7.94�1.22, p¼0.13) or lethaloutcomes (7.58�1.03 vs. 7.97�1.38, p¼0.41).

Conclusion: Our study did not confirm the value of MPV in predictingcomplications in the course of AP.

13 (2013) S2–S98 S31