Specific insulin-like growth factor-I receptors on circulating bovine mononuclear cells

J Recept Res. 1992;12(1):117-29. doi: 10.3109/10799899209066027.

Abstract

We have examined the presence and properties of specific receptors for IGF-I on bovine mononuclear cells. Competitive binding studies showed that binding of [125I]IGF-I to mononuclear cells was inhibited by unlabelled peptides with the rank of IGF-I greater than IGF-II greater than insulin. The binding of [125I]IGF-I was a function of the cell concentration. Equilibrium dissociation constant and receptor concentration values for the average of 9 adult cows were 1.13 +/- 0.11 nM and 108.9 +/- 24.1 fMol/10(7) cells, respectively. Moreover, IGF-I stimulated thymidine incorporation into bovine mononuclear cells in the absence of serum and phytohemagglutinin (PHA). The existence of specific and functional IGF-I receptors on circulating bovine mononuclear cells would provide an easily accessible source for studying IGF-I receptor changes in the bovine, both in physiologic and pathologic states.

MeSH terms

  • Animals
  • Cattle
  • Insulin-Like Growth Factor I / metabolism*
  • Leukocytes, Mononuclear / chemistry*
  • Receptors, Cell Surface / analysis*
  • Receptors, Somatomedin

Substances

  • Receptors, Cell Surface
  • Receptors, Somatomedin
  • Insulin-Like Growth Factor I