Kynurenic acid (KynA), an endogenous antagonist of N-methyl-d-aspartate (NMDA) glutamate receptors, protects the central nervous system in excitotoxic neurological diseases. We hypothesized that the inhibition of enteric glutamate receptors by KynA may influence dysmotility in the gastrointestinal tract. Group 1 of healthy dogs served as the sham-operated control, in group 2, the animals were treated with KynA, while in groups 3 and 4 mechanical colon obstruction was maintained for 7 h. Group 4 was treated with KynA at the onset of ileus. Hemodynamics and motility changes were monitored, and the activities of xanthine oxidoreductase (XOR) and myeloperoxidase (MPO) were determined from tissue samples. Colon obstruction induced a hyperdynamic circulatory reaction, significantly elevated the motility index and increased the mucosal leucocyte accumulation and the XOR activity. The KynA treatment augmented the tone of the colon, permanently decreased the motility index of the giant colonic contractions and reduced the increases in XOR and MPO activities. These effects were concomitant with the in vitro inhibition of XOR activity. In conclusion, KynA antagonizes the obstruction-induced motility responses and XOR activation in the colon. Inhibition of enteric NMDA receptors may provide an option to influence intestinal hypermotility and inflammatory changes.

The motility of the colon was either significantly increased or decreased, depending on the type and selectivity of the NOS inhibitor compounds applied. NO of neuronal origin is a transmitter that stimulates peristaltic activity; but an increased iNOS/nNOS ratio significantly moderates the obstruction-induced motility increase.

Background: Ischemic preconditioning (IPC) can provide a defense against ischemiaereperfusion (IR)-induced acute inflammation and barrier dysfunction in many organs. Because nitric oxide (NO) has been implicated as a trigger or mediator in the IPC mechanism and because neuronal NO synthase (nNOS) is a dominant isoform of NOS in the gastrointestinal tract, our aim was to investigate the role of nNOS in IPC-induced protection after mesenteric IR. Materials and methods: Intestinal IR was induced in sodium pentobarbitaleanesthetized dogs by clamping the superior mesenteric artery for 60 min followed by 2 h of reperfusion (IR group; n ¼ 7). In further groups, IPC was used (three cycles of 5-min ischemia/5-min reperfusion periods) before IR in the presence or absence of selective inhibition of nNOS with 7-nitroindazole (5 mg/kg, intravenously, in a bolus 15 min before IPC, n ¼ 6 each). Changes in mesenteric vascular resistance, intramucosal pH (pHi), and small bowel motility were monitored. Plasma nitrite/nitrate levels, intestinal NO synthase activity, leukocyte accumulation, mast cell degranulation, and histologic injury were also determined. Results: Ischemia significantly decreased mesenteric vascular resistance and pHi, whereas IR induced a temporary bowel hypermotility and acute inflammatory reaction. IPC facilitated pHi recovery, attenuated motility dysfunction, elevated NOS-dependent NO production, and reduced leukocyte accumulation, mast cell degranulation, and mucosal injury. Pretreatment with 7-nitroindazole halted the IPC-induced increase in NO availability, pHi recovery, and the anti-inflammatory and morphologic effects. Conclusions: Our data demonstrate that NO generated by intestinal nNOS plays a pivotal role in IPC-linked tissue protection by inhibiting an IR-related acute inflammatory response.

Introduction: Aneurysm of the extracranial carotid artery is a rare condition and there is a diversity in the etiology. The proper treatment could be a real challenge for the surgeons. Aim: Analysis of perioperative and long term results of invasive treatment for carotid artery aneurysm. Method: A retrospective review was conducted of patients who had open or endovascular surgery due to carotid artery aneurysm through the last 13 years at the Department of Vascular Surgery of the Semmelweis University and at the Department of Surgery of the University of Szeged. Medical history, characteristics of the aneurysms, therapy and the follow-up results were reviewed. Results: Over the study period, 25 interventions were performed due to carotid artery aneurysm. There were 10 men and 15 women with a mean age of 57.8 ± 15.15 years. Seventeen patients (68%) were symptomatic. The mean aneurysm diameter was 26.8 ± 11.25 mm. The underlying etiology was atherosclerosis in eleven (44%), prior carotid endarterectomy in four (16%), infection in four (16%) and other cause (connective tissue disease, dissection, trauma) in six (24%) cases. Nineteen patients underwent open surgery, six underwent endovascular treatment. Death within 30 days was documented in one (4%) case. The mean postoperative hospital stay was 4.52 ± 2.38 days. Three (12%) patients required reintervention postoperatively. Peripheral nerve injuries were detected in four (16%) patients, all after open surgery. No stroke was documented within 30 days. The mean follow-up was 41.2 ± 38.54 months. Five (24%) deaths were not related to the carotid artery disease. One patient had stroke, one had transient ischaemic attack (TIA), and in two cases asymptomatic internal carotid artery occlusion was described. Conclusion: Both open surgery and endovascular intervention can be safely applied in the treatment of carotid artery aneurysm. Considering the variable etiology and rarity, we recommend to perform the interventions in vascular surgery centres. Orv Hetil. 2019; 160(21): 815–821.

Összefoglaló. Bevezetés: Az endovascularis intervenciókat kezdetben radiológusok alkalmazták, manapság, megfelelő képzést követően, jó eredménnyel végeznek ilyen beavatkozásokat érsebészek is. Ezt a világszerte uralkodóvá váló szemléletet kívántuk meghonosítani a Szegedi Tudományegyetemen, melynek bevezetése nélkül előrevetíthető az érsebészet működésének átalakulása az érrekonstrukciós beavatkozások csökkenésével. Célkitűzés: Egyetemünkön radiológus- és érsebész-munkacsoport végez perifériás érintervenciókat. Célunk a két intézet alsó végtagi endovascularis tevékenységének összehasonlítása volt. Módszer: Vizsgálatunkba a Szegedi Tudományegyetemen 2012. 01. 01. és 2019. 12. 31. között alsó végtagi endovascularis beavatkozásokon átesett betegeket válogattuk be. A betegeket a rizikófaktoraik, a kezelt anatómiai régiók, a hospitalizációs idő és a szövődmények tekintetében hasonlítottuk össze. Egyéves utánkövetés során vizsgáltuk a ’redo’ műtétek , az amputációk és a halálozások gyakoriságát. Eredmények: A beavatkozásokat 653 esetben radiológus, 573 esetben érsebész végezte. Az érműtőben infrainguinalis (63,2%), a radiológián suprainguinalis érintervenciók (68,6%) történtek nagyobb arányban. A percutan végzett beavatkozásokat vizsgálva a hospitalizációs időben (2,5 ± 4,4 nap vs. 2,4 ± 2,5 nap, p = 0,78), valamint a minimálisan invazív módon végzett beavatkozások utáni szövődmények gyakoriságában (30/653 – 4,6% és 11/257 – 4,3%, p = 0,837) nem volt különbség a két betegcsoport között. ’Redo’ műtétek (73/485 – 15,1% és 33/562 – 5,9%, p<0,001) és amputációk (31/485 – 6,4% és 12/562 – 2,1%, p<0,001) gyakrabban fordultak elő az érműtőben kezelt betegek körében, ebben a csoportban azonban a kritikus végtagischaemia előfordulása is gyakoribb volt (45,4% és 38,6%, p = 0,016). A mortalitásban nem volt szignifikáns különbség (5,8% és 3,9%, p = 0,16). Következtetés: A szoliter érelváltozások kezelését mindkét intézet hasonló hatásfokkal végezte. A több anatómiai régiót érintő betegség miatt érműtőben végzett beavatkozások utáni szövődmények előfordulása kissé magasabbnak bizonyult. Orv Hetil. 2021; 162(24): 943–951. Summary. Introduction: Endovascular interventions were initially performed by radiologists. Nowadays properly trained vascular surgeons also effectively perform these interventions. We wished to apply this widespread practice at our university because without this advancement the number of reconstructive surgeries was expected to decrease significantly. Objective: Both radiologists and vascular surgeons perform endovascular interventions at our university. We compared the outcomes of lower extremity endovascular interventions between the two institutes. Method: We included patients who underwent lower extremity endovascular interventions between 01. 01. 2012 and 31. 12. 2019. We compared the risk factors, treated anatomical regions, hospitalization time and complication rate. During the one-year follow-up, we examined the occurrence of redo surgeries, amputations and mortality. Results: 653 interventions were performed by radiologists and 573 by vascular surgeons. Vascular surgeons carried out more interventions in the infrainguinal region (63.2%), while radiologists in the suprainguinal region (68.6%). The hospitalization time after percutaneous interventions (2.5 ± 4.4 days vs. 2.4 ± 2.5 days, p = 0.78), and the rate of complications after minimally invasive interventions did not show significant difference (30/653 – 4.6% vs. 11/257 – 4.3%, p = 0.837). Redo surgeries (73/485 – 15.1% vs. 33/562 – 5.9%, p<0.001) and amputations (31/485 – 6.4% vs. 12/562 – 2.1%, p<0.001) occurred more frequently in the surgical group. However, the incidence of chronic limb ischaemia was also higher (45.4% vs. 38.6%, p = 0.016). There was no significant difference in the mortality (5.8% vs. 3.9%, p = 0.16). Conclusion: Both institutes had similar efficacy in performing peripheral interventions on solitary vascular lesions. Complications occurred more frequently in the surgical group, but the majority of these patients had extended atherosclerotic diseases. Orv Hetil. 2021; 162(24): 943–951.