A quantitative study of the facial nerve in mice prenatally exposed to ethanol.
Pregnant ICR mice were given 20% ethanol intraperitoneally twice on day 13 of gestation and allowed to give birth to offspring. The offspring were killed at 56 days of age and the motor root of their facial nerve was examined histologically and morphometrically. The cross-sectional area of the facial nerve of mice prenatally exposed to ethanol was significantly smaller than that of the control mice. There was no significant difference in the total number of myelinated axons or the mean axonal diameter between control and ethanol-exposed mice, but the mean diameter of myelinated fibers (axon + myelin sheath) and the thickness of myelin sheath were significantly decreased in the treated group. These results suggest that prenatal exposure to ethanol disturbs myelination of the motor root of the facial nerve and may cause permanent neurological effects.
Komatsu
Suguru
S
Congenital Anomaly Research Center, Kyoto University Graduate School of Medicine, Yoshida Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan. komatsu@cac.med.kyoto-u.ac.jp
Sasaki
Yasuo
Y
Shiota
Kohei
K
D000818:Animals; D001369:Axons / Q000187:drug effects; D004195:Disease Models, Animal; D000431:Ethanol / Q000009:adverse effects*; D005154:Facial Nerve / Q000187:drug effects*; D005260:Female; D063647:Fetal Alcohol Spectrum Disorders / Q000209:etiology; D018811:Maternal Exposure; D051379:Mice; D008813:Mice, Inbred ICR; D008854:Microscopy, Electron; D009413:Nerve Fibers, Myelinated / Q000187:drug effects; D011247:Pregnancy; D011270:Pregnancy, Animal; D013997:Time Factors
D000431:Ethanol