Institute of Food, Nutrition and Human Health, Massey University, Private Bag 11222, Palmerston North, New Zealand.
J Comp Physiol B. 2012 Feb;182(2):287-97. doi: 10.1007/s00360-011-0610-2. Epub 2011 Sep 10.
We used high definition radial, strain rate and intensity spatiotemporal mapping to quantify contractile movements of the body and associated structures of the rabbit caecum when the terminal ileum was being perfused with saline at a constant rate. This perfusion caused gradual distension of the caecum as a result of relative restriction of outflow from the ampulla caecalis. The body of the caecum exhibited two patterns of motility that appeared autonomous, i.e. occurred independently of any contractile activity at the inlet or outlet. Firstly, the pattern that we termed ladder activity consisted of an orderly sequential contraction of bundles of axially oriented circular muscle between the spiral turns of longitudinal muscle and proceeded either from base to tip or from tip to base at a similar frequency and velocity. Secondly, less-localised, rapidly propagating synchronous contractions of both circular and longitudinal muscle, which were more common when the caecum was distended, that were termed mass peristalsis. Movements of the ileum and sacculus rotundus occurred at the same frequency and were broadly coordinated. Distension of the distal sacculus occurred synchronously with contraction of the ileum and did not propagate in an orderly manner across the structure, i.e. was instantaneous. This pattern was consistent with hydrostatic distension. Contractions propagated through the ampulla caecalis in either an orad or an aborad direction at a similar frequency to, and broadly correlated with, those in the ileum. The frequencies of distension of the sacculus and of contraction in the ileum and ampulla were momentarily augmented during mass peristalsis. The authors conclude that there was some coordination between the contractile activity of the terminal ileum and the caecal ampulla during periods of ongoing inflow from the ileum and between these structures and the caecum during mass peristalsis.
我们使用高清晰度的径向、应变速率和强度时空映射来定量测量兔盲肠的体部和相关结构的收缩运动，此时末端回肠以恒定速率被盐水灌注。这种灌流导致盲肠逐渐扩张，因为盲肠壶腹的流出相对受限。盲肠体部表现出两种运动模式，这些模式似乎是自主的，即独立于入口或出口的任何收缩活动发生。首先，我们称之为阶梯活动的模式由螺旋状纵向肌之间的轴向圆形肌束的有序顺序收缩组成，其进行方向可以是从基部到尖端或从尖端到基部，频率和速度相似。其次，较少局部的、快速传播的圆形和纵向肌肉同步收缩，当盲肠扩张时更为常见，我们称之为块状蠕动。回肠和圆囊的运动以相同的频率发生，并且广泛协调。远端圆囊的扩张与回肠的收缩同步发生，并且不会有序地在结构中传播，即瞬时发生。这种模式与静水压扩张一致。收缩通过盲肠壶腹以类似的频率向头侧或尾侧传播，与回肠中的收缩广泛相关。在块状蠕动期间，圆囊的扩张频率和回肠及盲肠壶腹的收缩频率会短暂增加。作者得出结论，在回肠持续流入期间，末端回肠和盲肠壶腹的收缩活动之间以及在这些结构和盲肠之间存在一定的协调性。
