Spontaneous migrating motor complexes occur in both the terminal ileum and colon of the C57BL/6 mouse in vitro.
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.
Bush
T G
TG
Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno 89557-0046, USA.
Spencer
N J
NJ
Watters
N
N
Sanders
K M
KM
Smith
T K
TK
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002799:Cholinergic Fibers / Q000187:drug effects / Q000502:physiology; D003106:Colon / Q000187:drug effects / Q000502:physiology*; D005260:Female; D018738:Hexamethonium / Q000494:pharmacology; D007082:Ileum / Q000187:drug effects / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL / Q000502:physiology*; D018727:Muscarinic Antagonists / Q000494:pharmacology; D016065:Myoelectric Complex, Migrating / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects; D018733:Nicotinic Antagonists / Q000494:pharmacology; D012727:Sex Characteristics; D013779:Tetrodotoxin / Q000494:pharmacology
D018727:Muscarinic Antagonists; D018733:Nicotinic Antagonists; D018738:Hexamethonium; D013779:Tetrodotoxin; D001285:Atropine