title: Effect of pentobarbital on the strength duration curve of the jaw opening reflex to tooth pulp stimulation in cats.
abstract: Brain stem field potentials and digastric electromyographic responses to tooth pulp stimulation were recorded in six chronically prepared adult cats. Strength duration curves were derived for both responses under conditions of wakefulness and anesthetic levels of sodium pentobarbital (35 mg/kg). For the muscle response, the slope of the strength duration curve for short duration pulses became more negative, and the chronaxies were significantly increased under anesthesia as compared to the awake state. For the field potential response, the same parameters were not significantly altered. The results suggest that the alteration in strength duration curve seen in the muscle response may be determined beyond the level of the first synapse.
mesh_terms: D000818:Animals; D001933:Brain Stem / Q000502:physiology; D002415:Cats; D003782:Dental Pulp / Q000294:innervation*; D004558:Electric Stimulation; D005071:Evoked Potentials; D008410:Masticatory Muscles / Q000294:innervation*; D008839:Microelectrodes; D009434:Neural Pathways; D010424:Pentobarbital / Q000494:pharmacology*; D011626:Pterygoid Muscles / Q000294:innervation*; D012018:Reflex / Q000187:drug effects* / Q000502:physiology
chemical_list: D010424:Pentobarbital