Glutamate-induced depression of EPSP–spike coupling in rat hippocampal CA1 neurons and modulation by adenosine receptors

The presence of high concentrations of glutamate in the extracellular fluid following brain trauma or ischaemia may contribute substantially to subsequent impairments of neuronal function. In this study, glutamate was applied to hippocampal slices for several minutes, producing over-depolarization, which was reflected in an initial loss of evoked population potential size in the CA1 region. Orthodromic population spikes recovered only partially over the following 60 min, whereas antidromic spikes and excitatory postsynaptic potentials (EPSPs) showed greater recovery, implying a change in EPSP–spike coupling (E–S coupling), which was confirmed by intracellular recording from CA1 pyramidal cells. The recovery of EPSPs was enhanced further by dizocilpine, suggesting that the long-lasting glutamate-induced change in E–S coupling involves NMDA receptors. This was supported by experiments showing that when isolated NMDA-receptor-mediated EPSPs were studied in isolation, there was only partial recovery following glutamate, unlike the composite EPSPs. The recovery of orthodromic population spikes and NMDA-receptor-mediated EPSPs following glutamate was enhanced by the adenosine A1 receptor blocker DPCPX, the A2A receptor antagonist SCH58261 or adenosine deaminase, associated with a loss of restoration to normal of the glutamate-induced E–S depression. The results indicate that the long-lasting depression of neuronal excitability following recovery from glutamate is associated with a depression of E–S coupling. This effect is partly dependent on activation of NMDA receptors, which modify adenosine release or the sensitivity of adenosine receptors. The results may have implications for the use of A1 and A2A receptor ligands as cognitive enhancers or neuroprotectants

One-Anastomosis Gastric Bypass Revision for Gastroesophageal Reflux Disease: Long Versus Short Biliopancreatic Limb Roux-en-Y Gastric Bypass

International audienceAbstractPurposeOne-anastomosis gastric bypass (OAGB) may be associated with refractory gastroesophageal reflux disease (GERD). The nature of this GERD remains unclear. This complication can be treated either with an additional enteroenterostomy without shortening of gastric pouch (long biliopancreatic limb Roux-en-Y gastric bypass (L-BPL-RYGB)) or revision to conventional short biliopancreatic limb Roux-en-Y gastric bypass (S-BPL-RYGB). The objective of this study is to compare the aforementioned procedures in terms of efficacy on GERD symptoms.Materials and MethodsRetrospective analysis between October 2012 and June 2020.ResultsFifty-two patients underwent OAGB revision to S-BPL-RYGB (n = 21) or L-BPL-RYGB (n = 31) secondary to GERD. Investigation with pH impedance prior to revision was performed in 15 patients showing biliary reflux (BR) in 7 (46.6%), acid reflux (AR) in 6 (40%), and no confirmation in 2. Patients with AR had a revision to S-BPL-RYGB, whereas patients with BR underwent L-BPL-RYGB. Among the patients without pH metry results (n = 37), S-BPL-RYGB was performed for associated disabling digestive disorders or nutritional deficiencies. GERD was treated in 68% of patients with L-BPL-RYGB versus 95% of patients after S-BPL-RYGB. Patients, whose decision for revisional procedure was based on the results of pH impedance testing, did not reveal refractory GERD.ConclusionL-BPL-RYGB seems appropriate in patients with BR, whereas conversion to S-BPL-RYGB should be preferred if AR is present

150-cm Versus 200-cm Biliopancreatic Limb One-Anastomosis Gastric Bypass: Propensity Score–Matched Analysis

International audienceBackgroundIt has been suggested that shortening the length of the biliopancreatic limb (BPL) to 150 cm in one anastomosis gastric bypass (OAGB) would reduce nutritional complication rates without impairing weight loss outcomes. The aim of this study is to compare patients who underwent OAGB with a 200-cm BPL (OAGB-200) to patients with OAGB with a 150-cm BPL (OAGB-150) in terms of weight loss and late morbidity.MethodsThis is a monocentric retrospective matched cohort study including patients with a body mass index between 35 and 50 kg/m2 who underwent an OAGB-150 or an OAGB-200. Patients were matched 1:1 based on age, sex, and body mass index, prior to bariatric surgery.ResultsIn total, 784 patients who underwent OAGB were included (OAGB-150 n = 392 and OAGB-200 (n = 392). There was no significant difference in terms of early morbidity. Regarding late morbidity in patients with an OAGB-150, significantly lower rates for marginal ulcer (OR = 0.4, CI 95% [0.2; 0.8], p = 0.006), incisional hernia (OR = 0.5, CI 95% [0.3; 1], p = 0.041), and bowel obstruction (OR = 0.3, CI 95% [0.1; 0.9], p = 0.039) were reported. Likewise, regarding late nutritional deficiencies, post-OAGB-150, a significantly lower number of patients with hypoalbuminemia (OR = 0.3, CI 95% [0.2; 0.7], p = 0.006), low vitamin B9 (OR = 0.5, CI 95% [0.2; 1], p = 0.044), and low ferritin (OR = 0.5, CI 95% [0.3; 0.8], p = 0.005) were observed. There was no significant difference in the percentage of excess BMI loss at 1, 2, 3, 4, and 5 years.ConclusionCompared to OAGB-200 in patients with BMI ≤ 50 kg/m2, OAGB-150 results in fewer nutritional deficiency rates long term, without impairing weight loss