Nystagmus induced by rotation of the body in the horizontal plane in postnatally growing rabbits
Schwartze, P.; Junghanns, J.
Acta Biologica et Medica Germanica 38(8): 1183-1191
1979
ISSN/ISBN: 0001-5318 PMID: 532496 Document Number: 145950
From 90 rabbits in chronic experiments, generally in the 5 days following the operation, electroocularographic leads were taken from the left bulbus oculi between the 1st-73rd day of life (DL). Nystagmus-like eye movements (NE) were elicited by rotary stimulation of the vestibular apparatus of the alert fixed animals (speed jump from 0-12.degree., 36.degree., 72.degree. and 120.degree./s) and subsequent further rotation with a constant speed for 15 s or by sinusoid movements in the horizontal plane (amplitude 20.degree., frequency 0.6 Hz, 0.4 Hz, 0.2 Hz and 0.06 Hz). The NE of the youngest animals (4th DL) showed the same speed against and in the direction of rotation. Up to the 8th DL, NE patterns typical for adults developed; NE consisted of a slow and a rapid component. The frequency to react to rotary stimulation with generation of NE, the number of NE during stimulation and NE overall amplitude increases with the age of the animals. The latency from the onset of stimulation to the 1st NE coincides with age the more distinctly the animals slower than the rate are turned. The time intervals between the 1st 10 NE during continuous rotation decrease from the 20th DL onward. The capacity of generating vestibularly initiated NE in the rabbit develops in the 1st 20 DL. Some parameters, such as the number of NE during continuous rotary stimulation vary still up to an age of 2.5 mo. This behavior is apparently caused more by functional change of the relay nuclei and external eye muscles than by change of the vestibular apparatus.