Electrical behavior of myenteric neurons in XXXX distal colon.

@entity3798 @entity1025 @entity840 @entity1022 @entity141
Intracellular recording was used in vitro to analyze electrophysiological properties of neurons in myenteric ganglia of @entity840 distal colon. The neurons were classified into six types based on their electrical behavior. Type 1 colonic neurons discharged action potentials throughout depolarizing current pulses and were otherwise similar to S/type 1 neurons found in the @entity840 small bowel. The second type had passive and active electrical properties similar to those of @entity3798 /type 2 myenteric neurons of the small intestine. These cells discharged only a single spike at the onset of depolarizing current pulses, and the spikes were followed by long-lasting hyperpolarizing afterpotentials. Excitability of the type 2 neurons was enhanced in the presence of elevated Mg2+ and reduced @entity141 , and the spikes were unaffected by tetrodotoxin. Type 3 colonic neurons showed fast synaptic potentials but did not generate action potentials. The majority of neurons were referred to as type 2 colonic neurons. Type 4 neurons discharged single action potentials only at the onset of depolarizing current pulses, and the spikes were not followed by prolonged hyperpolarizing afterpotentials. Unlike type 2 neurons, excitability remained unchanged in the presence of reduced extracellular @entity141 and elevated @entity1025 . Action potentials of type 4 neurons were suppressed or abolished by @entity1022 . A group of spontaneously active neurons was classified as type 5 colonic neurons. Type 6 cells were inexcitable and assumed to be glial cells.
