Activation of splanchnic and pelvic colonic afferents by bradykinin in mice
Activation of splanchnic and pelvic colonic afferents by bradykinin in mice
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DOI：
10.1111/j.1365-2982.2005.00710.x
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发表时间：
2005-12-01
影响因子：
3.5
通讯作者：
Blackshaw, LA
中科院分区：
文献类型：
--
作者：
Brierley, SM;Jones, RCW;Blackshaw, LA
背景：腰内脏神经（LSN）和骶盆神经（PN）从结肠向脊髓传递不同的机械感觉信息。在这里，我们确定这些途径是否不同，也在他们的化学敏感性缓激肽。方法：使用一种新的体外小鼠结肠制备，serenum传入记录从LSN和PN和区分基于他们的mechanosensitivity冯弗雷丝（70-4000毫克）和不敏感性结肠拉伸（1-5克）或精细粘膜中风（10毫克）。结果：臂丛神经和脊神经对机械刺激有不同的动力学反应，脊神经对机械刺激的反应强度较低，反应强度大，反应持续时间长。缓激肽（1 μ mol L-1）兴奋66%（27 41）的LSN传入。缓激肽后探测的反应增强。B-2受体拮抗剂HOE-140（10 nmol L-1）可逆转浓度依赖性（EC 50：0.16 μ mol L-1）反应。12个缓激肽反应传入是机械不敏感的。对缓激肽有反应的LSNs传入纤维多于PN传入纤维（11%，P < 0.001），且反应更大（P < 0.05）。没有机械不敏感的PN传入招募缓激肽。结论：缓激肽有力地刺激大多数内脏serenchnic传入通过B-2-受体，但很少骨盆传入。缓激肽募集的机械不敏感传入神经仅限于LSN。
Background: Lumbar splanchnic (LSN) and sacral pelvic (PN) nerves convey different mechanosensory information from the colon to the spinal cord. Here, we determined whether these pathways differ also in their chemosensitivity to bradykinin.Methods: Using a novel in vitro mouse colon preparation, serosal afferents were recorded from the LSN and PN and distinguished based on their mechanosensitivity to von Frey filaments (70-4000 mg) and insensitivity to colonic stretch (1-5 g) or fine mucosal stroking (10 mg). Bradykinin was applied into a ring around mechanoreceptive fields.Results: The LSN and PN afferents had different dynamic responses to mechanical stimuli: PN afferents required lower intensity stimuli, evoked larger responses, and displayed more maintained responses than LSN afferents. Bradykinin (1 mu mol L-1) excited 66% (27 of 41) of LSN afferents. Responses to probing were potentiated after bradykinin. The concentration-dependent (EC50: 0.16 mu mol L-1) response was reversed by the B-2-receptor antagonist HOE-140 (10 nmol L-1). Twelve bradykinin responsive afferents were mechanically insensitive. More LSN serosal afferents responded to bradykinin than PN afferents (11%, P < 0.001), with larger responses (P < 0.05). No mechanically insensitive PN afferents were recruited by bradykinin.Conclusions: Bradykinin potently stimulates most splanchnic serosal afferents via B-2-receptors, but few pelvic afferents. Mechanically insensitive afferents recruited by bradykinin are exclusive to the LSN.