Body weight in mouse embryos specifies staging of tooth development.
Great intra- and interlitter variation in morphological stages is known to exist among mouse embryos of the same strain at a similar chronological stage. With the aim of searching for an easily measurable parameter that correlates well with tooth development, the morpho- and histodifferentiation of teeth were compared in embryos classified according to the embryonic day (ED) specified by wet body weight. The embryos and fetuses were harvested at 12-h intervals from ED12.5 until birth, weighed, fixed, and processed histologically. The tooth age was determined according to the developmental progress of the first molar, evaluated based on morpho- and histodifferentiation criteria. The data documented a better correlation between tooth morpho-histodifferentiation with the age/weight staging than with only the embryonic day. The cyto-differentiation of odontoblasts exhibited a high interlitter variability and was similar within specimens of the same litter, regardless of their body weight differences.
Peterka
M
M
Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague 4, Czech Republic. peterka@biomed.cas.cz
Lesot
H
H
Peterková
R
R
D000818:Animals; D001835:Body Weight; D004622:Embryo, Mammalian / Q000033:anatomy & histology / Q000502:physiology; D005314:Embryonic and Fetal Development; D051379:Mice / Q000196:embryology*; D008813:Mice, Inbred ICR; D009804:Odontoblasts / Q000166:cytology; D009805:Odontogenesis / Q000502:physiology*