Ginkgolide B accelerates vestibular compensation of spontaneous ocular nystagmus in guinea pig following unilateral labyrinthectomy.
The aim of this study was to investigate the effects of ginkgolide B on the behavioral recovery process (vestibular compensation) which occurs following surgical removal of the vestibular receptor cells in one labyrinth (unilateral labyrinthectomy, UL). Guinea pigs received a single ip injection of ginkgolide B at the time of the UL (25, 50, or 100 mg/kg) and the effects on the compensation of the UL symptoms, spontaneous ocular nystagmus (SN), yaw head tilt (YHT), and roll head tilt (RHT), were evaluated. The effects of a single vehicle injection or a similar injection of ginkgolide A were used for comparison. Twenty-five mg/kg ginkgolide B significantly increased the rate of SN compensation compared to the vehicle control group (P < 0.02). However, 50 mg/kg ginkgolide B had no significant effect on either SN frequency or the rate of SN compensation. Ginkgolide B (100 mg/kg) significantly altered the rate of SN compensation (P < 0.02); however, SN frequency values were higher at most measurement times. YHT and RHT were not significantly affected by ginkgolide B at any of the doses used. Twenty-five mg/kg ginkgolide A had no significant effect on any of the UL symptoms. These results suggest that, at the optimal dose of 25 mg/kg, a single ip injection of ginkgolide B at the time of the UL can produce an acceleration of SN compensation.
Maclennan
K
K
Department of Psychology, University of Otago, Dunedin, New Zealand.
Smith
P F
PF
Darlington
C L
CL
D000818:Animals; D003289:Convalescence; D004224:Diterpenes; D004305:Dose-Response Relationship, Drug; D007758:Ear, Inner / Q000293:injuries*; D005133:Eye Movements / Q000187:drug effects*; D005260:Female; D046934:Ginkgolides; D006168:Guinea Pigs; D006257:Head; D007783:Lactones / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D009759:Nystagmus, Pathologic / Q000503:physiopathology*; D011187:Posture; D014722:Vestibule, Labyrinth / Q000187:drug effects / Q000502:physiology*
D004224:Diterpenes; D046934:Ginkgolides; D007783:Lactones; C045856:ginkgolide B