we show that membranes from newly differentiated chick embryo tissues ( day 6 brain , day 6 heart , day 8 liver , day 12 skeletal muscle ) as well as whole embryos postneurulation ( day 2 , stage of 27-30 somites ) have two populations of receptors with distinct specificity : insulin and type i igf ( igf-i ) receptors .
C0037657
igf
C0021665
igf-i