Biomaterial Database

Improved preparation of Xenopus oocytes for patch-clamp recording. 1997

H Choe, and H Sackin

Department of Physiology and Biophysics, Cornell University Medical College, 1300 York Ave., New York NY 10021, USA.

We report a new technique for improving the efficiency of single-channel recording in the Xenopus oocyte expression system. Conventional methods of oocyte preparation (adequate for two-electrode voltage-clamp) often leave residual adhesions between the vitelline and plasma membranes. As a result, removal of the vitelline membrane for patch-clamp recording produces microscopic damage to the oocyte plasma membrane that interferes with the formation of high-resistance electrical seals. This problem has been alleviated by a three-phase method of oocyte preparation: (1) a strong initial enzymatic digestion using both collagenase and hyaluronidase, immediately followed by (2) exposure to hypertonic media and mechanical defolliculation, (3) pre-shrinkage and selection of only those oocytes displaying clear separation between vitelline and plasma membranes. Following this selection process, oocytes were returned to solutions of normal osmolarity, incubated overnight at 19 degrees C, and then injected with RNA for expression studies. Comparison of oocytes prepared by different methods indicated that use of these three steps significantly improved the success of high-resistance seal formation, without compromising oocyte survivability or the efficiency of channel expression.

UI	MeSH Term	Description	Entries
D009865	Oocytes	Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).	Ovocytes,Oocyte,Ovocyte
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D005260	Female		Females
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014817	Vitelline Membrane	The plasma membrane of the egg.	Membrane, Vitelline,Membranes, Vitelline,Vitelline Membranes
D014982	Xenopus laevis	The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.	Platanna,X. laevis,Platannas,X. laevi
D018408	Patch-Clamp Techniques	An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.	Patch Clamp Technique,Patch-Clamp Technic,Patch-Clamp Technique,Voltage-Clamp Technic,Voltage-Clamp Technique,Voltage-Clamp Techniques,Whole-Cell Recording,Patch-Clamp Technics,Voltage-Clamp Technics,Clamp Technique, Patch,Clamp Techniques, Patch,Patch Clamp Technic,Patch Clamp Technics,Patch Clamp Techniques,Recording, Whole-Cell,Recordings, Whole-Cell,Technic, Patch-Clamp,Technic, Voltage-Clamp,Technics, Patch-Clamp,Technics, Voltage-Clamp,Technique, Patch Clamp,Technique, Patch-Clamp,Technique, Voltage-Clamp,Techniques, Patch Clamp,Techniques, Patch-Clamp,Techniques, Voltage-Clamp,Voltage Clamp Technic,Voltage Clamp Technics,Voltage Clamp Technique,Voltage Clamp Techniques,Whole Cell Recording,Whole-Cell Recordings