Embryologic features of term fetuses and newborns in CL/Fr mice with special reference to cyanosis.
OBJECTIVE
The objective of this study was to clarify the embryologic features of CL/Fr mice in relation to cyanosis.


METHODS
Orofacial examinations were conducted on 18-day-old term fetuses and newborns. Except for open eyelids in a few cases, all of the external abnormalities in this strain were cleft lip and/or palate (CLP).


RESULTS
The CLP incidence in term fetuses was 28.4%. The body and placental weights were not different between CLP(+) and CLP(-) fetuses. Several types of CLP were found; the most frequent was bilateral complete CLP (60%) followed by left complete (16%). Bilateral complete CL, which is the most severe CL type, was associated with poorly developed secondary palate and wide cleft. In newborns, 39.4 % of CLP(+) mice showed cyanosis, where no CLP(-) mice had such signs. The body weight of cyanotic mice with CLP was significantly lighter than that of noncyanotic mice with CLP. Cyanotic mice had severe types of CLP and unelevated palatal shelves.


CONCLUSIONS
We suggest that mechanical airway obstruction may be one of the causes of cyanosis in newborn CL/Fr mice.
Kadowaki
S
S
Department of 1st Anatomy, Kinki University, School of Medicine, Osaka, Japan.
Sakamoto
M
M
Kamiishi
H
H
Tanimura
T
T
D000402:Airway Obstruction / Q000150:complications / Q000196:embryology; D000818:Animals; D000831:Animals, Newborn; D002972:Cleft Palate / Q000196:embryology* / Q000209:etiology; D003490:Cyanosis / Q000150:complications / Q000196:embryology*; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000150:complications / Q000196:embryology; D008297:Male; D051379:Mice; D008817:Mice, Mutant Strains; D009296:Nasal Cavity / Q000002:abnormalities / Q000196:embryology; D010159:Palate / Q000002:abnormalities / Q000196:embryology