title: Long term effects of prenatal exposure to low level gamma rays on spontaneous circadian motor activity of male mice.
abstract: The spontaneous circadian motor activity of first generation (F1) hybrid male C57BL/6xC3H mice irradiated with gamma rays on the 14th day of gestation was studied at the following ages: young (6-7 months), adult (12-13 months), and old (19-20 months). Doses were 0.1, 0.2, 0.5 or 1.0 Gy. A 12-hour day-night cycle was maintained with light on a at 6:00 hr. Spontaneous circadian motor activity was recorded with a capacitance-induction motility monitor for 48 consecutive hours. Activity was measured at 2-hour intervals, and the data stored on computer discs. The activity of the 1.0 Gy group recorded at 22:00 and 2:00 hr for young mice and at 2:00 hr for adult ones was significantly higher than that of the age-matched control group. Results suggest that male mice irradiated with 1.0 Gy at gestational day 14 show nocturnal hyperactivity in the young and adult stages.
authors.affiliation: Department of Biology, Yamanshi Medical University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Minamisawa
authors.forename: K
authors.initials: K
authors.lastname: Hirokaga
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002940:Circadian Rhythm / Q000528:radiation effects*; D005260:Female; D005720:Gamma Rays / Q000009:adverse effects; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000528:radiation effects*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011829:Radiation Dosage