Basic and Clinical investigation for disordered defecation after low anterior resection

直肠前切除术（AR）伴淋巴结清扫术后，即使肛门直肠功能恢复，也经常观察到排便习惯的改变，这可能是由于术后结肠动力的变化。本研究旨在探讨外源性自主神经损伤程度与结肠动力改变的关系。[方法]将12只杂种犬随机分为4组，每组5只。A组在腹主动脉旁和骶前区的自主神经，包括腹下神经和盆丛，从肠系膜尾动脉（CMA）的轴水平到盆腔空间。B组在CMA轴至髂动脉分叉处的主动脉旁区域进行去神经支配。C组沿CMA至腹膜反射处的边缘动脉沿着切断结肠系膜。D组仅植入电极。肌电图 ...更多信息 在消化间期状态下30分钟和通过胃造口术注射橄榄油后120分钟期间连续测量aphic活性。每隔10 min计数连续电反应活动（CERA）和收缩性电复合波（CEC）。[结果]术后3周，A组注射橄榄油后20 ~ 30 min和30 ~ 40 min的结肠CERA和CEC分别为2.2 <plus-minus>± 0.72，3.4 <plus-minus>± 1.12<plus-minus>，均小于D组的10.6 <plus-minus>± 1.97，10.8 ± <plus-minus>2.24（P&lt;0.05）。即使在右侧结肠中也存在这种差异（A组：0.4 <plus-minus>± 0.28，0.6 <plus-minus>± 0.40 ; D组：4.3 <plus-minus>± 0.98，4.3 ± <plus-minus>0.91 ; p&lt;0.05）。B组和C组消化间期CERA和CEC分别为8.8 <plus-minus>± 1.87和7.6 <plus-minus>± 1.45，与D组（5.2 ± 0.83）比较，差异有显著性（p&lt;0.05）<plus-minus>。术后4个月，B组和C组结肠动力恢复到D组水平，但A组右侧结肠动力仍较低（0.8 <plus-minus>± 3.32，0.4 ± <plus-minus>3.32 ; p&lt;0.05）。[结论]盆丛在结肠运动中起重要作用，即使是右半结肠也是如此。副交感神经突触前神经元的损伤至少在失神经支配后4个月才能恢复。提示盆腔神经丛损伤可引起AR术后排便习惯改变

After anterior resection of the rectum (AR) with lymph node dissection, change in bowel habit is often observed even after recovery of the anorectal function possibly due to changes in colonic motility after the operation. This study was to investigate the relationship between the degrees of extrinsic autonomic nerve injury and the changes in colonic motility. [Methods] Twelve mongrel dogs were equally divided into four groups and underwent implantation of 5 serosal electrodes on the colon. Group A had denervation of autonomic nerves in the paraaortic and presacral regions, including hypogastric nerve and pelvic plexus, from the level of the axis of the caudal mesenteric artery (CMA) to the pelvic space. Group B had denervation in the paraaortic region from the axis of the CMA to the bifurcation of the iliac artery. Group C had denervation by dividing the mesocolon along the marginal artery from the CMA to the peritoneal reflection. Group D had only electrode implantation. Electromyogr … More aphic activity was measured continuously during 30 minutes in interdigestive state and 120 minutes after injection of olive oil through gastrostomy. The number of continuous electrical response activity (CERA) and contractile electrical complex (CEC) were counted in every ten minutes. [Results] Three weeks after the operation, colonic CERA and CEC in the period from 20 to 30 and 30 to 40 minutes after the olive oil injection was smaller (p<0.05) in Group A (2.2<plus-minus>0.72,3.4<plus-minus>1.12, respectively ; mean<plus-minus>SEM) than in Group D(10.6<plus-minus>1.97,10.8<plus-minus>2.24). This difference was present even in the right-sided colon (Group A : 0.4<plus-minus>0.28,0.6<plus-minus>0.40 ; Group D : 4.3<plus-minus>0.98,4.3<plus-minus>0.91 ; p<0.05). On the other hands, CERA and CEC in the interdigestive state in Group B (8.8<plus-minus>1.87)and C(7.6<plus-minus>1.45) were increased (p<0.05) as compared with Group D (5.2<plus-minus>0.83).Four months after the operation, increased colonic motility in Group B and C returned to the level of Group D,but the low colonic motility was still observed in the right-sided colon in Group A (0.8<plus-minus>3.32,0.4<plus-minus>3.32 ; p<0.05). [Conclusions] Pelvic plexus plays an important role in colonic motility even of the right-sided colon. The damage to theparasympathetic presynaptic neurons did not recover at least until 4 months after denervation. These data suggest that the pelvic plexus injury may cause the change in bowel habit after AR Less