[Effect of potassium ions on the electrical activity of ampullae of Lorenzini in the skate].
Effect of different concentration of externally applied K+ on the resting and evoked discharge of the isolated Lorenzini ampullae was studied in skates. It was shown that low K+ or K+-free solutions caused a decrease in the frequency of the afferent discharge. An increase in K+ concentration (6-10 mM) produced a reversible increase in the resting activity, with no effect on the receptor thresholds to electrical stimulation. When synaptic transmission was abolished by Mg+2 (30-40 mM) an increase in K+ concentration induced no activity in the afferent nerve discharge. However if L-glutamate was added to the Mg+2-containing solution, it partially restored the activity and addition of K+ caused an additional increase in the existing activity.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D004338:Drug Combinations; D005071:Evoked Potentials / Q000187:drug effects; D005399:Fishes / Q000502:physiology*; D005971:Glutamates / Q000494:pharmacology; D018698:Glutamic Acid; D008274:Magnesium / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology / Q000502:physiology*; D012679:Sense Organs / Q000502:physiology*
D004338:Drug Combinations; D005971:Glutamates; D018698:Glutamic Acid; D008274:Magnesium; D011188:Potassium
Vliianie ionov kaliia na élektricheskuiu aktivnost' ampul Lorentsini skatov.