TABLE 2.

Comparison of wild-type and Cpr−/− embryos at 9.5 dpc from dams with altered RA supplya

GenotypeTreatment (mg/kg)Axial rotationPairs of somitesBranchial archesHeart formationNeural tubePresence of limb budsNo. of examined embryos
Cpr+/+/Cpr+/−NoneYes18-263Asymmetric loopedClosedYes>300
RA (5)Yes18-262 or 3Looped, enlargedClosedYes28
RA (7.5)Yes16-210 or 1Asymmetric enlargedOpen0-2 forelimb buds27
VADYes18-263Asymmetric loopedClosedYes42
Cpr−/−None (P1)Yes12-160Symmetric, enlargedOpenNo>60
None (P2)No8-120Symmetric enlargedOpenNo>140
RA (5)No<100Symmetric enlargedOpenNo3
RA (7.5)3 (resorptions)
VADYes16-190AsymmetricOpenNo9
VADNo160AsymmetricOpenNo1
  • a Dams were gavaged with 7.5 or 5 mg of atRA/kg (n = 3 for each concentration) at 7.5 and 8.5 dpc or fed a normal diet or a VAD diet (n = 6), and embryos were harvested at 9.5 dpc. Note that no Cpr−/− embryos of mothers given a high dose of RA were identified, but three placentas found in the three litters contained resorbed material with a Cpr−/− genotype.