[Guinea pig as often object to otoneurological experimental examinations].
BACKGROUND
The aim of this research was to describe nomograms of brainstem auditory evoked potentials, oscillating stimulation of the vestibular organs and ultrastructural research methodology of a spiral organ of guinea-pigs.


METHODS
For the experimental purposes 60 guinea-pigs of both sexes, weight 250-300 grams, were used as research materials. After general anesthesia with Ketalar dosed 100 milligrams per kilogram and with Fentanyl dosed 0.1 milliliter per kilogram of the body mass, brainstem auditory evoked potentials were registered and the oscillating chair test (no prior anesthesia). Was placed on an assistant's knees, who was sitting on a chair. Then the guinea-pigs were anesthetized with 35 per cent solution of chloral hydrate intraperitoneally (dosed 1 milliliter per kilogram of the body mass). For electron microscopic research membranous helix was collected bilaterally by the method of micropreparation. Qualitative observation was conducted in the Philips' electron microscope (EM 300).


RESULTS
On the basis of the obtained results it was concluded that the time of transmission between elements P1-P2 is constant and figures between 3.1 and 3.6 ms independently from a force of stimulation. Vestibular organs of a guinea-pig are more sensitive to high accelerations (17-12 degree/s2) than human vestibularl organs. However, their reaction is much weaker to lower accelerations (12-0 degree/s2).


CONCLUSIONS
The processed nomograms of the brainstem auditory evoked potentials, oscillating stimulation of vestibular organs and methodology of ultrastructural research in guinea-pigs' spiral organs are expected to facilitate using them in experimental research.
Olszewski
Jurek
J
Klinika Otolaryngologii i Onkologii Laryngologicznej II Katedry Otolaryngologii UM w Lodzi. jolszewski@poczta.onet.pl
D000818:Animals; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D008297:Male; D014724:Vestibular Function Tests; D014722:Vestibule, Labyrinth / Q000502:physiology*