The Xenoplace workstation is designed to be a simple yet comprehensive workstation for investigating the electrical properties of Xenopus Oocytes.
Oocytes are useful in electrophysiology and pharmacology research because the pre-emergent egg is basically a factory ready to make a frog, and therefore able to process a wide variety of RNA. As such it is very capable of processing the RNA that codes for membrane ion channels and can easily express those channels in the membrane of the egg. Since a typical egg is about 1mm across, millions to billions of channels can be expressed giving rise to large currents that can be more easily studied than in a neuron or other excitable tissue.
The large size of the egg can give rise to other electrical problems that must be dealt with such as large capacitance and high current. A good amplifier such as the TEC 03 from npi makes the perfect system to use with the Xenoplace since is contains many of the features necessary to discriminate membrane currents and give accurate recordings.
The typical Xenoplace set-up consists of the TEC amplifier from npi and two MM-33 manipulators mounted on a base plate. The two manipulators are positioned so that electrodes can descend into a chamber to pierce an oocyte which can also be perfused, very easily with drugs, or other substances.
The chamber, specifically, and the design layout were perfected by Lonnie Wollmuth in his lab at SUNY Stony Brook in Long Island, New York. The system provides two manipulators, one for the measuring electrode and one for the current injecting electrode. There is a unique channel with a dimple to hold the oocyte, and two reference electrode (AgCl pellets) are positioned adjacent to the dimple.
Convenient plug-in connections allow the user to connect the reference electrodes to the head stage. Perfusion liquid entering the chamber is channeled directly at the oocyte. Fluid is removed via a suction port from just behind the oocyte, or from a Luer connection on the side of the chamber block. There is a pedestal catch basin that supports the chamber and serves to catch the liquid if the removal system should fail. A clip holds the current injecting head stage for convenience. All the components are tied to a common base plate for convenience and stability.
The Xenoplace Chamber consists of the following:
* npi TEC-03X High performance two-electrode voltage clamp amplifier with model cell
* ALA VC3-4PG 4 channel gravity fed perfusion system
* 2 x MM-33 mechanical manipulators
* ALA’s small volume Xenoplace™ Recording Chamber with built-in reference electrodes
* Set of electrode holders, current headstage adapter, and model cell
* Binocular microscope with boom stand.