Dantrolene diminishes forelimb force-related tremor at doses that do not decrease operant behavior in the rat.
A behavioral preparation that affords concurrent measurement of forelimb force and tremor in rats was used to assess the effects of dantrolene sodium, a muscle relaxant and potential neuroprotective drug. Rats that were trained to press downward on an isometric force transducer while simultaneously licking water reinforcement were administered dantrolene (5.0 mg/kg, 7.5 mg/kg, and 10.0 mg/kg). Dantrolene diminished force output at the 7.5 mg/kg and 10.0 mg/kg doses and decreased tremor at all three doses. Dantrolene decreased the ratio of forelimb tremor to force output at all three doses. Dantrolene did not suppress operant behavioral output at these doses. These results suggest that dantrolene may affect fine motor control and decrease tremor at doses that do not produce behavioral suppression.
Stanford
John A
JA
Department of Anatomy and Neurobiology, University of Kentucky Chandler Medical Center, Lexington 40536-0098, USA. jastan2@uky.edu
Fowler
Stephen C
SC
D000818:Animals; D001522:Behavior, Animal; D003216:Conditioning, Operant / Q000187:drug effects*; D003620:Dantrolene / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D005552:Forelimb; D008297:Male; D009125:Muscle Relaxants, Central / Q000627:therapeutic use*; D005082:Physical Exertion; D011597:Psychomotor Performance / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time; D012054:Reinforcement, Psychology; D014202:Tremor / Q000188:drug therapy*
D009125:Muscle Relaxants, Central; D003620:Dantrolene