The hyperinsulinemic-euglycemic clamp is the "gold standard" for the assessment of insulin action. Insulin is infused at a constant rate stimulating glucose uptake. The amount of exogenous glucose infused to counter this drop is indicative of insulin sensitivity. Here the procedure is performed on a conscious, unrestrained rat.
Application of a Mouse Ligated Peyer’s Patch Intestinal Loop Assay to Evaluate Bacterial Uptake by M cells
M cells in a specialized follicle-associated epithelium covering Peyer’s patches play an important role for the mucosal immunosurveillance in gut-associated lymphoid tissue. Here we described the evaluation method for bacterial transcytosis by M cells in vivo. This method provides a method to understand M-cell function in the immune system.
1Department of Biomedical Engineering, Washington University in St. Louis
The cut-open Vaseline gap approach is used to obtain low noise recordings of ionic and gating currents from voltage-dependent ion channels expressed in Xenopus oocytes with high resolution of fast channel kinetics. With minor modification, voltage clamp fluorometry can be coupled to the cut-open oocyte protocol.
In situ patch clamp recordings are used for electrophysiological characterization of neurons in intact circuitry. In the Drosophila genetic model patch clamping is difficult because the CNS is small and surrounded by a robust sheath. This article describes the procedure to remove the sheath and clean neurons for subsequent patch clamp recordings.
Implementing Dynamic Clamp with Synaptic and Artificial Conductances in Mouse Retinal Ganglion Cells
1Discipline of Biomedical Science, School of Medical Sciences, Sydney Medical School and Bosch Institute, University of Sydney, 2The MARCS Institute, University of Western Sydney, 3Discipline of Physiology, School of Medical Sciences, Sydney Medical School and Bosch Institute, University of Sydney
This video article illustrates the set-up, the procedures to patch cell bodies and how to implement dynamic clamp recordings from ganglion cells in whole-mount mouse retinae. This technique allows the investigation of the precise contribution of excitatory and inhibitory synaptic inputs, and their relative magnitude and timing to neuronal spiking.
Published May 16, 2013. Keywords: Neuroscience, Neurobiology, Biomedical Engineering, Anatomy, Physiology, Molecular Biology, Cellular Biology, Neurons, Retinal Neurons, Retinal Ganglion Cells, Eye, Retina, Neurosciences, retina, ganglion cells, synaptic conductance, artificial conductance, tetrodotoxin (TTX), patch clamp, dynamic clamp, conductance clamp, electrophysiology, mouse, animal model
The amperometric technique measures dopamine release from a single cell by detecting the oxidative current produced by spontaneous dopamine oxidization. Simultaneous voltage clamp and amperometry methodology reveal the mechanistic relationship between the overall "activity" of dopamine transporter and the regulatory role of this activity on the reverse transport of dopamine.
Published November 21, 2012. Keywords: Neuroscience, Cellular Biology, Physiology, Medicine, Simultaneous Patch Clamp and Voltametry, In Vitro Voltametry, Dopamine, Oxidation, Whole-cell Patch Clamp, Dopamine Transporter, Reverse transport, Efflux
Application of a NMDA Receptor Conductance in Rat Midbrain Dopaminergic Neurons Using the Dynamic Clamp Technique
In this video, we demonstrate how to apply a conductance into a dopaminergic neuron recorded in the whole cell configuration in rat brain slices. This technique is called the dynamic clamp.
This video shows how to use a programmable puller to make patch pipettes and sharp electrodes for electrophysiology. The same procedure can be used to make a variety of glass tools, including injection needles.
1Department of Biology, Case Western Reserve University
Understanding the role of environmental heterogeneity in species coexistence has typically focused on types of heterogeneity that are extrinsic to the community’s species composition. We provide novel detailed methods for creating soil heterogeneity treatments using soils subject to plant-soil feedback conditioning, or heterogeneity intrinsic to the community composition.
Surgical Procedures for a Rat Model of Partial Orthotopic Liver Transplantation with Hepatic Arterial Reconstruction
1Institute for Laboratory Animal Science and Experimental Surgery, RWTH-Aachen University, 2Department of Hepato-Biliary-Pancreatic Surgery and Transplantation, Graduate School of Medicine, Kyoto University
Orthotopic liver transplantation in rats is an indispensable experimental model for biomedical research. Here we present our surgical procedures for orthotopic rat liver transplantation with hepatic arterial reconstruction using a 50% partial graft.
Published March 7, 2013. Keywords: Medicine, Biomedical Engineering, Anatomy, Physiology, Immunology, Surgery, liver transplantation, liver, hepatic, partial, orthotopic, split, rat, graft, transplantation, microsurgery, procedure, clinical, technique, artery, arterialization, arterialized, anastomosis, reperfusion, rat, animal model