Torpedo cells

In the following the Cl -channels will be subdivided into those of the central nervous system, of muscle and Torpedo electroplax, of apolar non-excitable cells and of epithelia. 

Very few of the CP-channels described above have been purified, and the amino acid sequence is only known for the GABAA-receptor channel, the glycine-receptor channel and the Torpedo CP-channel [3-5], a CP-channel from skeletal muscle [125] and a CP-channel from MDCK cells [128]. In the following the current status will be briefly summarized. 

The Xenopus oocyte can reliably express LGIC receptors. In our laboratory, we have seen robust expression of the Torpedo nAChR, 5-HT3 receptors and various GABAa receptor subtypes in oocytes. Injection of cRNA transcripts is a convenient and reproducible way to achieve the expression levels needed for functional analysis of receptor subtypes. We have found that functional characterization with this system complements biochemical experiments conducted on native receptors or those that have been expressed in mammahan cells. A combination of these approaches is essential for furthering our understanding of structure-function relationships in these receptors. 

One variant of the liquid cathode reserve battery is the lithium-water cell in which water serves as both the liquid cathode and the electrolyte. A certain amount of corrosion occurs, but sufficient lithium is provided to compensate. These cells are mostly used in the marine environment where water is available or compatible with the cell reaction product. Common applications are lor torpedo propulsiuu and to puwer sonobuoys and submersihles. 

Nicotinic receptor from Torpedo californica Receptor was fixed into a cross-linked poly(vinylbutyral) membrane covering the gate of an ISFET which was mounted in a sample cell with a reference ISFET and Ag-AgCl reference electrode. Sensitive to ACh, H +, Na + and K +. Steady state reached after 2 min. Initial rate of change of the voltage was a rectilinear function of log ACh concentration was a from 0.1 to 10 pM. When receptor was immobilized in the membrane by using lecithin an amplified response was obtained which was due to Na + flux across receptor channel. [65]... 

Figure 9.2. Sketch of a Torpedo electric organ, a Several thousand disk-like cells are stacked up. Only one of the membranes is excitable by way of nicotinic acetylcholine receptors (NAR) and voltage-gated channels (not shown). In the resting state, the membrane potential is the same on both membranes in each cell, and the electric field vectors cancel out. b Upon excitation, the top membrane of each cell is depolarized. Now, all electrical field vectors point into the same direction and add up to a total voltage of several hundred Volts.

Secondary batteries Portable electronic devices cell phones, cordless phones, laptops, camcorders, toys. Communications satellites, military radios. Transportation electric vehicles, car ignition batteries. Defense torpedoes, missiles. 

Automobiles cost more than 100 times the price of the battery, but the battery permits easy, reliable starting, allowing it to be a convenient mode of transportation for normal lifestyles. Indeed, batteries provide the only efficient small-scale devices for the storage of instantly available electrical energy. Dependent on batteries are all automobiles all telephone circuits most modem watches, calculators, and standby power sources most modem weapons systems for propulsion (torpedoes, for example), communication, and guidance systems space exploration (which also uses fuel cells) and implanted heart pacers. 

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