Conversion of a gonadotropin-releasing hormone antagonist to an agonist

@article{Conn1982ConversionOA,
  title={Conversion of a gonadotropin-releasing hormone antagonist to an agonist},
  author={P. Michael Conn and Deloris C. Rogers and John M Stewart and James E. Niedel and T Sheffield},
  journal={Nature},
  year={1982},
  volume={296},
  pages={653-655}
}
Gonadotropin-releasing hormone (pyroGlu1-His2-Trp3-Ser4-Tyr5-Gly6-Leu7-Arg8-Pro9-Gly10 amide, GnRH) stimulates pituitary luteinizing hormone (LH) release. An antagonist, D-pyroGlu1-D-Phe2-D-Trp3-D-Lys6-GnRH (GnRH-Ant), binds to the pituitary GnRH receptor and inhibits GnRH-stimulated (10−9 M) gonadotropin release from pituitary cultures (IC50 = 2 × 10×7 M). GnRH-Ant has no measurable agonist activity at concentrations up to 10−6 M. The presence of the D-Lys6 both affords protection against… Expand
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