Sand Elin, Themner-Persson Anna, Ekblad Eva
Department of Experimental Medical Science, Unit Neurogastroenterology, Lund University, BMC, B11, SE 22184 Lund, Sweden.
Neuropharmacology. 2009 Feb;56(2):522-30. doi: 10.1016/j.neuropharm.2008.10.007. Epub 2008 Oct 25.
Mast cell-nerve interactions play a key role in intestinal inflammation and irritable bowel disease. Loss of enteric neurons has been reported in inflammatory conditions but the contribution of mast cells in this event is unknown. To study neuronal survival and plasticity of myenteric neurons in contact with mast cells a co-culture system using myenteric neurons from rat small intestine and peritoneal mast cells was set up. Dissociated myenteric neurons were cultured for 4 days before addition of mast cells isolated by peritoneal lavage. Neuronal survival and expression of vasoactive intestinal peptide (VIP) and nitric oxide synthase (NOS) were studied by immunocytochemistry and neuronal cell counting. Myenteric neurons cultured without mast cells were used to study the rate of neuronal survival after the addition of various mast cell mediators, proteinase-activated receptor(2) (PAR(2)) agonist, VIP or corticosteroid. A striking mast cell-induced neuronal cell death was found after co-culturing. It was counteracted by the addition of mast cell stabiliser doxantrazole, protease inhibitors, PAR(2) antagonist FSLLRY-amide, corticosteroid or VIP. In myenteric neurons cultured without mast cells the PAR(2) agonist SLIGRL-amide, prostaglandin D(2) and interleukin (IL) 6 reduced neuronal survival while histamine, serotonin, heparin, IL1beta and tumour necrosis factor alpha had no effect; corticosteroid and VIP enhanced neuronal survival. The relative numbers of VIP-, but not NOS-expressing myenteric neurons increased after co-culturing. Mast cell-induced neuronal cell death is suggested to be mediated via PAR(2) activation, IL6 and prostaglandin D(2). Corticosteroid and VIP are neuroprotective and able to prevent cell death of myenteric neurons in co-culture.
肥大细胞与神经的相互作用在肠道炎症和肠易激综合征中起关键作用。在炎症状态下已报道存在肠神经元缺失，但肥大细胞在此过程中的作用尚不清楚。为了研究与肥大细胞接触的肌间神经丛神经元的存活及可塑性，建立了一种共培养系统，该系统使用大鼠小肠的肌间神经丛神经元和腹膜肥大细胞。解离的肌间神经丛神经元培养4天后，加入通过腹膜灌洗分离的肥大细胞。通过免疫细胞化学和神经元细胞计数研究神经元存活以及血管活性肠肽（VIP）和一氧化氮合酶（NOS）的表达。未与肥大细胞共培养的肌间神经丛神经元用于研究加入各种肥大细胞介质、蛋白酶激活受体2（PAR2）激动剂、VIP或皮质类固醇后的神经元存活率。共培养后发现肥大细胞显著诱导神经元细胞死亡。加入肥大细胞稳定剂多克沙唑、蛋白酶抑制剂、PAR2拮抗剂FSLLRY-酰胺、皮质类固醇或VIP可抵消这种作用。在未与肥大细胞共培养的肌间神经丛神经元中，PAR2激动剂SLIGRL-酰胺、前列腺素D2和白细胞介素（IL）6降低神经元存活率，而组胺、5-羟色胺、肝素、IL-1β和肿瘤坏死因子α则无影响；皮质类固醇和VIP提高神经元存活率。共培养后，表达VIP的肌间神经丛神经元相对数量增加，但表达NOS的神经元数量未增加。肥大细胞诱导的神经元细胞死亡被认为是通过PAR2激活、IL-6和前列腺素D2介导的。皮质类固醇和VIP具有神经保护作用，能够预防共培养中肌间神经丛神经元的细胞死亡。
