title: Head-up behavior induced by low-doses of X-irradiation in the mouse and its disappearance by zinc sulfate perfusion in the nasal passage.
abstract: X-rays are commonly said to be one of many stimulus agents which are not perceivable by the sensory organs of mammals. However, I observed an interesting phenomenon where a mouse lifted its head and looked up (head-up behavior) while keeping its body flat on the floor when a mouse was given low-doses whole-body X-irradiation emitted from above. An attempt was made to examine whether mice could discern the direction of an X-ray source. I observed EEG responses and the head-up behavior when the mice were exposed to 4 cGy X-rays from more than one angle. The results showed that the mice awoke immediately and displayed the head-up behavior when those showing non-REM sleep were given 4 cGy X-rays emitted from above, below or from the side of the mouse. Mice showing REM sleep, however, showed no such behavior. Furthermore, the head-up behavior was not observed at all, even after 4 cGy X-irradiation, when the mouse was deprived of its olfactory sense by ZnSO4 solution. These results show that mice could detect low-doses of X-rays, without knowing the direction of the source, and peripheral olfactory cells were possibly involved in this detection.
authors.affiliation: Department of Physiology, Toho University School of Medicine, Ohmori-nishi 5-21-16 Ohta-ku, Tokyo 143, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Miyachi