Phosphorylation levels of K_V4.3 and K_V2.2 in normal, sham, and obstruction groups.

<p>Phosphorylation of Kv4.3 and Kv2.2 were examined by immunoprecipitation (IP) with ant-Kv4.3 antibody followed by IB with antibody against p-threonine, p-serine and Kv4.3 or IP with anti- Kv2.2 antibody followed by IB with antibody against p-threonine, p-serine and Kv2.2 (A). Corresponding bands were scanned and the phosphorylation band optical density was normalized by the total protein density. Data were the means ± SD and were expressed as folds versus normal. *<i>P</i><0.05 versus normal and sham, n = 5 (B).</p

Kv4.3 and Kv2.2 expressions of intestinal smooth muscle tissues in normal, sham, and obstruction groups.

<p>A shows the westernblot bands performed with anti-Kv4.3 or anti- Kv2.2 antibodies to detect the Kv4.3 and Kv2.2 expression levels. GAPDH was used as internal control to normalize for difference in loading. Corresponding bands were scanned and the Kv4.3 or Kv2.2 band optical density was normalized by the GAPDH protein density. Data showed the means ± SD, n = 6, *<i>P</i><0.05 versus sham groups (B).</p

Changes of slow wave and resting membrane potential (RMP) in hypertrophic smooth muscles.

<p>Electrical slow waves were recorded from small intestinal muscle stripes of normal group (Aa), sham group (Ab), and obstruction group (Ac). The RMP (Ba), amplitudes (Bb) and frequencies (Bc) of slow wave were significantly changed in normal, sham and obstruction groups. Data showed the means ± SE *<i>P</i><0.01 versus sham and normal groups.</p

Comparison of IK_V in normal sham and obstruction groups.

<p>A shows representative current traces elicited from a holding potential of −60 mV using voltage steps of 400 ms from −40 mV to +100 mV in 20 mV increments. Interval between each pulse is 10 s. Averaged current density-voltage relation of IK_Vpeak (B) and IK_Vsustained (C) plotted for the smooth muscle cells from normal, sham, and obstruction groups. Data showed the means ± SE *<i>P</i><0.01 versus sham and normal groups.</p

The hypertrophy of smooth muscle cells induced by partial intestinal obstruction.

<p>A shows normal (a) and hypertrophic smooth muscle cells (b), the cell size was significantly enlarged in obstruction group. B shows the mean values of cell capacitances among normal, sham and obstruction groups. Data showed the means ± SE *P<0.01 versus sham and normal groups, *<i>P</i><0.05 versus normal and sham group, Bar = 100 µm.</p

Comparison of the sensitivities of IK_V to 4-AP and TEA in normal, sham and obstruction groups.

<p>Membrane currents elicited by 400−60 mV to +40 mV in control or in 4-AP 5 mM (A) or TEA 5 mM (B). Interval between each pulse is 10 s. Average dose-response curves of 4-AP (C) and TEA (D) where each point was the averaged I_test/I_control and error bars were means ± SE. IC₅₀ values were obtained through the software GraphPad Prism 5.</p

Comparisons of voltage-dependent activation and inactivation of IK_V in normal, sham and obstruction groups.

<p>Aa shows representative raw traces were elicited by a series of voltage champs from a holding potential of −60 mv to selected test potentials ranging from −50 to +60 mV for 400 ms. Interval between each pulse is 10 s. Voltage-dependent activation of IK_Vpeak (Ab) and IK_Vsustained (Ac) were respectively converted into conductivity using the Goldman-Hodgkin-Katz current equation. The conductivies were the normalized and plotted as a function of test potential and fitted with a Boltzmann function. Ba shows representative current traces of IK_V were elicited by a series of the conditioning potential ranging from −100 to 0 mV for 500 ms following a 0 mV test potential for 400 ms. Bc shows current traces of IK_V were elicited by a series of the conditioning potential ranging from −100 to 0 mV for 20 s following 40 mV test potential to adequately activate the IK_Vsustained. Interval between each pulse is 10 s (Ba c). Voltage-dependent inactivation curves of IK_Vpeak (Bb) and IK_Vsustained (Bd) were plotted as a function of the conditioning potential and fitted with a Boltzmann function. Data showed the means ± SE(Ab c, Bb c).</p

Immunofluorescence staining of K_V4.3 in the mice small intestine frozen section.

<p>The cell membrane was stained by Fm 4-64 membrane stain (red fluorescence) and cell nuclear was stained by DAPI (blue fluorescence). The green fluorescence was KV4.3 immunofluorescence. Scale bar = 20 µm, the experiments repeated six times.</p