Sequential changes of potassium currents in Hermissenda type B photoreceptor during early stages of classical conditioning.
Classical conditioning of the marine snail Hermissenda can be produced in a single session of 50 pairings of light and rotation stimuli. Voltage clamp measurements of two outward K+ currents, IA and ICa2(+)-K+ were obtained from medial Type B photoreceptors that were isolated from the nervous system 1 day after animals were exposed to paired light and rotation stimuli or control procedures (Unpaired, or no exposure to light and rotation), ICa2(+)-K+ was found to be unchanged 18-30 h after 50 training trials. This result is consistent with a previous study where ICa2(+)-K+ was found to be unchanged after 50 light and rotation trials, although significantly reduced by 100 trials. In the present study 50 pairings of light and rotation produced a significant reduction in IA, suggesting an important role for this current in the earliest stages of classical conditioning.
Lederhendler
I I
II
Laboratory of Molecular and Cellular Neurobiology, NINDS, NIH, Bethesda, MD 20892.
Collin
C
C
Alkon
D L
DL
D000818:Animals; D003214:Conditioning, Classical / Q000502:physiology*; D066298:In Vitro Techniques; D008564:Membrane Potentials; D010775:Photic Stimulation; D010786:Photoreceptor Cells / Q000166:cytology / Q000502:physiology*; D011188:Potassium / Q000502:physiology*; D012908:Snails / Q000502:physiology*
D011188:Potassium