Medical Journal of the Islamic Republic Of Iran
مجله پزشکی جمهوری اسلامی ایران
Med J Islam Repub Iran
Medical Sciences
http://mjiri.iums.ac.ir
2
journal2
1016-1430
2251-6840
8
10.18869/mjiri
14
8888
13
en
jalali
1377
8
1
gregorian
1998
11
1
12
3
online
1
fulltext
en
HYPERVITAMINOSIS A-INDUCED CENTRAL NERVOUS SYSTEM DEFECTS
Anatomical Sciences
Anatomical Sciences
Original Research: Basic Science in Medicine
Original Research: Basic Science in Medicine
In this investigation the effects of excess vitamin A administration during the
early embryonic period were studied. Intramuscular injection of a single dose of
15000,20000 or 25000 IU/kg vitamin A to pregnant Balb/c strain mice on either day
7,8,9 or 10 of gestation (vaginal plug= day 0 of gestation) produced major
malformations in the central nervous system (CNS) including exencephaly,
hydrocephalus, microcephalia, spina bifid a and myelocystocele and also a few other
defects such as limb malformations. The incidence and severity of these malformations
was positively correlated with the dosage and time of exposure. Among experimental
groups, the most effective dose of vitamin A which produced a high incidence of
CNS defects was 25000 IU/kg injected on day 8 of gestation (35%) compared to the
control group (0%). Histological studies on 18 day old experimental fetuses revealed
spina bifid a with and/or without spinal cord defect. These studies showed excessive
embryonic cell death localized in the neural tube region following vitamin A
exposure. In conclusion, excess vitamin A exposure in the early days and critical
periods of development may interfere with certain developmental phenomena,
resulting in various detectable CNS defects among newborn infants.
Vitamin A, neural tube defect, neurolation.
279
283
http://mjiri.iums.ac.ir/browse.php?a_code=A-10-298-458&slc_lang=en&sid=1
MEHDI
JALALI
20031947532846004793
20031947532846004793
Yes
From the Department of Anatomy, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Islamic Republic of Iran.
ALIREZA
FAZEL
20031947532846004794
20031947532846004794
No