1. Intracellular microelectrodes were used to record spontaneous and evoked inhibitory junction potentials (IJP) from the circular muscle layer of the mid-distal region of the @entity19 isolated colon in the presence of @entity594 (1 micromol/L) and @entity5591 (1 micromol/L). 2. The length of the tissue preparation (> 1 cm) or the presence of the mucosa had no effect on the frequency of spontaneous IJP. 3. @entity4033 (500 micromol/L) reduced the frequency of spontaneous IJP to approximately 70% of the control frequency, whereas @entity2899 (280 micromol/L) reduced the frequency to approximately 17% of control. @entity3855 (250 nmol/L) abolished all spontaneous IJP activity. 4. The greater inhibition of spontaneous IJP in the presence of @entity2899 compared with @entity4033 is discussed as a possible 'apamin-like' effect. 5. Although electrically evoked IJP (single pulse at 15 V, 0.6 msec) were not significantly affected by @entity4033 , @entity2899 and apamin reduced the amplitude of evoked IJP to approximately 65 and 50% of control, respectively. 6. These results suggest that the properties of spontaneous IJP cannot be inferred by a study of evoked IJP alone.

Ongoing nicotinic and non-nicotinic inputs to inhibitory neurons in the XXXX colon.

@entity4033 :: ('MESH:D018738', 'Chemical') :: ['Hexamethonium', 'hexamethonium'] @entity3855 :: ('MESH:D001030', 'Chemical') :: ['Apamin'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity594 :: ('MESH:D009543', 'Chemical') :: ['nifedipine'] @entity5591 :: ('MESH:D012601', 'Chemical') :: ['hyoscine'] @entity2899 :: ('MESH:D014403', 'Chemical') :: ['D-tubocurarine']
@entity19 :: (10090,Species) :: ['mouse']
