Diabetes, Vol 37, Issue 5 585-589, Copyright © 1988 by American Diabetes Association
Autoradiographic evidence for insulin and insulin-like growth factor binding to early mouse embryos
BA Mattson, IY Rosenblum, RM Smith and S Heyner
Department of Anatomy and Cell Biology, Tufts University, School of Medicine, Boston, Massachusetts 02111.
Insulin binding to mouse oocytes and preimplantation embryos was assessed
by light-microscopic autoradiography. Significant insulin binding was
present on the cells of morulae and increased twofold at the blastocyst
stage of development. Insulin binding was markedly decreased by native
insulin and to a lesser extent by insulin-like growth factors (IGFs). No
specific insulin binding was detected on oocytes or embryos throughout the
eight-cell stage. Specific binding of IGF-I and IGF-II was also observed on
the cells of blastocyst outgrowths. The findings demonstrate that specific
binding of insulin and IGF is temporally expressed on the cells of pre- and
peri-implantation mouse embryos. These results confirm and extend our
previous immunofluorescence study.