Biomaterial Database

Isolated perfused salamander proximal tubule: methods, electrophysiology, and transport. 1981

H Sackin, and E L Boulpaep

Techniques are presented for the isolation and perfusion of renal proximal tubules from the neotenic salamander Ambystoma tigrinum. Methods are described for a determination of normal values for fluid transport and electrophysiological parameters. Stable cellular microelectrode recordings are reported that constitute the first intracellular measurements in an isolated perfused tubule preparation. With identical solutions in lumen and bath, fluid reabsorption averaged 0.28 nl.min-1.mm-1, transepithelial potential difference averaged -4.5 mV, transepithelial resistance was 52.1 omega.cm2, and the transepithelial chloride-to-sodium transference number ratio was 3.4. The basolateral cell membrane potential difference averaged -59.6 mV, and the ratio of apical-to-basolateral cell membrane resistance was between 3.9 and 5. Viability of the isolated perfused salamander proximal tubule preparation is demonstrated by a detailed comparison of the present data with results of in vivo micropuncture experiments on both Necturus and intact Ambystoma kidneys. In addition to being an advantageous preparation for long-term intracellular recordings, the Ambystoma kidney is unique in that proximal tubules can be studied both in isolation and by conventional micropuncture.

UI	MeSH Term	Description	Entries
D007687	Kidney Tubules, Proximal	The renal tubule portion that extends from the BOWMAN CAPSULE in the KIDNEY CORTEX into the KIDNEY MEDULLA. The proximal tubule consists of a convoluted proximal segment in the cortex, and a distal straight segment descending into the medulla where it forms the U-shaped LOOP OF HENLE.	Proximal Kidney Tubule,Proximal Renal Tubule,Kidney Tubule, Proximal,Proximal Kidney Tubules,Proximal Renal Tubules,Renal Tubule, Proximal,Renal Tubules, Proximal,Tubule, Proximal Kidney,Tubule, Proximal Renal,Tubules, Proximal Kidney,Tubules, Proximal Renal
D007814	Larva	Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.	Maggots,Tadpoles,Larvae,Maggot,Tadpole
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D008564	Membrane Potentials	The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).	Resting Potentials,Transmembrane Potentials,Delta Psi,Resting Membrane Potential,Transmembrane Electrical Potential Difference,Transmembrane Potential Difference,Difference, Transmembrane Potential,Differences, Transmembrane Potential,Membrane Potential,Membrane Potential, Resting,Membrane Potentials, Resting,Potential Difference, Transmembrane,Potential Differences, Transmembrane,Potential, Membrane,Potential, Resting,Potential, Transmembrane,Potentials, Membrane,Potentials, Resting,Potentials, Transmembrane,Resting Membrane Potentials,Resting Potential,Transmembrane Potential,Transmembrane Potential Differences
D008839	Microelectrodes	Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed)	Electrodes, Miniaturized,Electrode, Miniaturized,Microelectrode,Miniaturized Electrode,Miniaturized Electrodes
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D004553	Electric Conductivity	The ability of a substrate to allow the passage of ELECTRONS.	Electrical Conductivity,Conductivity, Electric,Conductivity, Electrical
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D005260	Female		Females
D000557	Ambystoma	A genus of the Ambystomatidae family. The best known species are the axolotl AMBYSTOMA MEXICANUM and the closely related tiger salamander Ambystoma tigrinum. They may retain gills and remain aquatic without developing all of the adult characteristics. However, under proper changes in the environment they metamorphose.	Amblystoma,Ambystoma tigrinum,Tiger Salamander,Amblystomas,Ambystomas,Salamander, Tiger,Salamanders, Tiger,Tiger Salamanders