[Effect of acceleration on the sugar content of rabbit cerebrospinal fluid]

The sugar content in the liquor of rabbits exposed to accelerations ranging from several minutes to several hours was studied. The animals were accelerated at 3 g in a centrifuge with a radius of 55 cm and a velocity of 70 rpm, in the Khilov's swing and in a rotating device simulating angular accelerations. The liquor was sampled by the suboccipital puncture and the sugar content was measured according to Hagedorn-Jensen. A statistically significant increase in the sugar content was noted after every exposure to accelerations of alternating signs than with accelerations of a constant value. The experiments on labyrinth-ectomized animals showed a certain effect of the vestibular analyzer on the carbohydrate metabolism. However, when the equilibrium function reached compensation, the sugar content in the liquor returned to the pretest level. Therefore, this reaction involves not only the vestibular system but also the optic, proprio- and interoceptive afferent systems. A comparison of the intracysternal and intramuscular injections of epinephrine points to the central (in contrast to the hematogenic) nature of an increase in the sugar content during the first minutes of acceleration. The electric stimulation of the anterior and posterior hypothalamus by means of implanted electrodes produced the same elevation of the liquor sugar as accelerations. It can be postulated that afferent impulses from the analyzer systems reach the hypothalamic centers, thus exciting the autonomic system and, first of all, the sympathic system.