Electrophysiologic experiments

Electrophysiological Experiments. Guinea pig myocardial cells prepared as described previously 24) were superfused at 37 C with a Tyrode solution. Electrical properties of the myocytes were examined by the patch-clamp methods (25) using fire-polished pipettes. The current was measured by means of a patch-clamp amplifier, stored on the tape through a digital PCM data recording system, and analyzed with a computer. 

The electrophysiological experiments reported here and done with patch-clamp techniques support this idea. The external application of MTX to isolated cardiac myocytes caused a sustained inward current which was carried by Ca . MTX did not increase the voltage-dependent Ca channel current, and both the time dependence and voltage dependence of the MTX-induced current were clearly different from those of the usual Ca channel current. These results suggest that the MTX-induced steady current is different from the usual voltage-dependent Ca channel current, and that this is possibly a current which flows through a new type of Ca -permeable channel. Tbe steady current described here may be responsible for the highly enhanced Ca influx induced by MTX and could account for the excitatory action of MTX on smooth and cardiac muscles. 

Cultures of Gambierdiscus toxicus have been obtained in several laboratories (14,17-19). These cultures produce large amounts of maitotoxin and low amounts of lipid-soluble CTx-like toxin. However, in most cases, this toxin has not been unequivocally identified as CTx. The only firm evidence that cultures of Gambierdiscus toxicus produce CTx was provided by Baden et al. (20) who used radioimmunoassays and electrophysiological experiments to characterize the toxin. It is possible that cultured Gambierdiscus toxicus produce only trace amounts of CTx and that levels of production comparable to those found in natural populations are dependent on yet undefined environmental parameters. 

The interaction of neurotoxins with the Na channel are usually studied using electrophysiological experiments, Na uptake experiments, and also binding experiments involving radiolabelled toxins. 

In vitro transcribe the large amounts of aptamers needed for electrophysiological experiments using the Megascript kit (Ambion). 

In Hugh Piggin s electrophysiology experiments, did they try resetting manipulations in the dish that avoided PACAP receptors Can the tissue be provoked into something rhythmic This would get around the possibility. One outside possibility is that this is a SCN that had never seen light and had never been synchronized it had never become competent to be rhythmic. 

For an electrophysiological experiment you form an electrode from a 5 cm long platinum wire (0.4 mm diameter) by bending it in the shape of a spiral. Calculate the total capacitance of the diffuse electric double layer for aqueous solutions of a monovalent salt at concentrations of 0.1 and 0.001 M. Assume a low surface potential. 

It has to be noted that the electrophysiological experiments in which 3,5-DHPG exclusively caused inhibition of EPSP amplitude in hippocampal slices were carried... 

Fig. 1. Behavioral response and hippocampal synaptic transmission during exposure to open field stress in freely moving rats. Behavior analysis and electrophysiological experiments were performed simultaneously during the postadolescent period (10-12 weeks old). (A) Locomotor activity estimated by total crossings for 30 min and (B) time-course of crossings during exposure to open field stress. (C) Time-course of population spike amplitude (PSA) in the hippocampal CA1 field evoked by Schaffer collaterals stimulation. Values are expressed as a percentage of the baseline level before open field stress. Non-FS, pups exposed to the footshock (FS) box without FS 2W-FS and 3W-FS, pups exposed to FS during the second and third postnatal weeks, respectively. Each value represents the mean S.E.M. p < 0.05 versus non-FS controls (modified from Koseki etal., 2007).

Electrophysiological experiments to determine the relative abilities of contact chemoreceptors to perceive E, 20E and PoA in larvae of Mamestra brassicae [40], Bombyx mori, Spodoptera littoralis and Ostrinia nubilalis [118], In M brassicae a specific cell is present in the lateral sensilla of the maxilla which responds to 20E and PoA, but not to E. In B. mori, the medial sensilla were responsive to 20E and PoA, but not E. This finding confirmed previous observations [39], Both lateral and medial sensilla were responsive to E, 20E and PoA in O. nubilalis, with a... 

Recently electrophysiological experiments by Sasz have yielded results which would indicate that not only periplanone-B, but also periplanone-A could be a genuine pheromone. With single cell recording techniques he demonstrated the presence of many olfactory hairs on the antennae of Periplaneta americana that were very sensitive to periplanone-A, whereas others were sensitive for periplanone-B (41). 

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