Related Experiment Video
Updated: Aug 14, 2026

Channelrhodopsin2 Mediated Stimulation of Synaptic Potentials at Drosophila Neuromuscular Junctions
Published on: March 16, 2009
Properties of channels mediating the apamin-insensitive afterhyperpolarization in vagal motoneurons
1Neuroscience Group, Faculty of Medicine and Health Sciences, University of Newcastle, Australia.
Abstract:
1. Whole cell recordings were obtained from neurons of the dorsal motor nucleus of the vagus in transverse slices of guinea pig medulla. From a holding potential of -40 mV, short depolarizing voltage steps activated two calcium-dependent potassium currents, Gk(Ca),1 and Gk(Ca),2. 2. Gk(Ca),1 was completely blocked by apamin (100 nM). Gk(Ca),2 was apamin insensitive, voltage independent, and reversed close to the potassium equilibrium potential. 3. Activation of Gk(Ca),2 was associated with an increase in current variance. The channels underlying the slow component were analyzed by stationary and nonstationary fluctuation analysis. Current variance was linearly related to mean current for small current amplitudes but clearly deviated from linearity near the peak of Gk(Ca),2. The predicted single channel conductance was 6.8 +/- 2.5 (SE) pS. Probability of channel opening rose to at most 0.68. The average number of available Gk(Ca),2 channels on vagal neurons was 4,437 +/- 591. 4. Power spectra were constructed from the peak current. Spectra were well fitted with a single Lorentzian with a corner frequency of 72 +/- 7 Hz. The mean burst duration of the channels was 3.8 +/- 0.5 ms. These results indicate that a new type of calcium-activated channel underlies Gk(Ca),2.
More Related Videos
11:02Exploring Arterial Smooth Muscle Kv7 Potassium Channel Function using Patch Clamp Electrophysiology and Pressure Myography
Published on: September 14, 2012
08:11Voltage-Dependent Potassium Current Recording on H9c2 Cardiomyocytes via the Whole-Cell Patch-Clamp Technique
Published on: November 11, 2022
Related Concept Videos
Voltage-gated Ion Channels
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
G-Protein Gated Ion Channels
Sensory organs,...
Cholinergic Receptors: Muscarinic
The subtypes M1, M3, and M5 couple with the Gq subunit and activate the phospholipase C (PLC) activity, mobilizing intracellular Ca2+. Activation...
Nondepolarizing (Competitive) Neuromuscular Blockers: Mechanism of Action
Competitive antagonists prevent acetylcholine from binding to its receptor, inhibiting membrane depolarization. Without conformational changes or intrinsic...
Parasympathetic Signaling
The effects of...
Voltage-gated Ion Channels
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...