Bush T G, Spencer N J, Watters N, Sanders K M, Smith T K
Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno 89557-0046, USA.
Auton Neurosci. 2000 Nov 1;84(3):162-8. doi: 10.1016/S1566-0702(00)00201-0.
We have studied migrating motor complexes (MMCs) in the isolated terminal ileum or colon (IMMCs and CMMCs respectively) of the C57BL/6 mouse. Periodic contractions occurred spontaneously in both preparations in the absence of intraluminal stimulation. After an initial period, complexes became synchronized between the oral and anal ends of the tissue, and could be observed for in excess of 7 h. The propagation velocity was 3.1+/-1.0 and 3.9+/-0.6 mm s(-1) in the ileum and colon respectively. IMMCs occurred every 6.01+/-0.39 min and had a duration of 86.3+/-10.4 s. The interval between CMMCs was smaller (3.52+/-0.31 min) and contractions were shorter in duration (30.7+/-3.6 s). In both preparations, these motor events were dependent on cholinergic transmission: blocked by hexamethonium (500 microM) and attenuated or blocked by atropine (1 microM). This study is the first demonstration of spontaneous migrating contractions in the isolated ileum or colon of the C57BL/6 mouse, the strain of choice for neurological transgenic and targeted mice.
我们研究了C57BL/6小鼠离体回肠末端或结肠中的移行性运动复合波（分别为IMMCs和CMMCs）。在无腔内刺激的情况下，两种标本均自发出现周期性收缩。在初始阶段后，复合波在组织的口端和肛端之间变得同步，并且可以观察超过7小时。回肠和结肠中的传播速度分别为3.1±1.0和3.9±0.6 mm s⁻¹。IMMCs每6.01±0.39分钟出现一次，持续时间为86.3±10.4秒。CMMCs之间的间隔更短（3.52±0.31分钟），收缩持续时间更短（30.7±3.6秒）。在两种标本中，这些运动事件均依赖于胆碱能传递：被六甲铵（500μM）阻断，并被阿托品（1μM）减弱或阻断。本研究首次证明了C57BL/6小鼠离体回肠或结肠中存在自发移行性收缩，该品系是神经学转基因和靶向小鼠的首选品系。
