Main Content

The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Ref ID : 7415

Christian Stock, Thomas Kruppel, and Wolfgang Lueken; Kinesis in Euplotes vannus -Ethological and Electrophysiological Characteristics of Chemosensory Behavior. J.Eukaryot.Microbiol. 44(5):427-433, 1997

Reprint

In File

Notes

Equally dispersed Euplotes vannus cells accumulate inside a drop of supernatant of a bacteria suspension that is surrounded by a reference solution. In the drop, frequencies of stops and backward jerks are tenfold increased. The sequences of directional changes and translocations prevent cells from leaving the chemostimulant region, as if they were trapped. This behavior is quickly induced after casual arrival in the drop and not by chemotactic influence over a larger distance. With intracellular recodings, we have found a K+ conductance decrease is chemically stimulated cells that prolongs the duration of spontaneously occurring depolarizations to 600-1,700 msec by delaying repolarization. The freely fluctuating membrane potential shifts to more depolarized levels, although the total potential range is expanded in the positive and negative direction by 5.5 and 3.8 mV, respectively. Chemosensory behavior is explained and discussed with respect to these electrophysiological events.