Effects of paraoxon on spike initiation and conduction block in the giant interneurons of the American cockroach, Periplaneta americana.
1. The effects of paraoxon were studied on spike initiation and conduction in the giant interneurons (GIs) of the American cockroach, using electrophysiological techniques. 2. Paraoxon treatment induced high-frequency bursts in GI axons. During these bursts, overshooting spikes recorded in the sixth abdominal ganglion were replaced, in phase, by small, decremental potentials. 3. These small potentials were not EPSPs since current injection could modulate their frequency. 4. An analysis of anteriorly conducted spikes indicates that the site of spike initiation is located near the dendritic region of the GI and is unchanged by paraoxon treatment.
Heppner
T J
TJ
Dept. of Anatomy and Neurobiology, University of Vermont, Burlington 05405.
Drewes
C D
CD
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001369:Axons / Q000187:drug effects; D003058:Cockroaches / Q000187:drug effects*; D007395:Interneurons / Q000187:drug effects*; D009431:Neural Conduction / Q000187:drug effects; D010261:Paraoxon / Q000494:pharmacology*; D010526:Periplaneta / Q000187:drug effects*
D010261:Paraoxon