Patent ID: 6924268

Claim:
A method for using at least one hormone/toxin conjugate to sterilize an animal, said conjugate comprising a peptide hormone binding to a GnRH receptor, conjugated by a linking agent to a toxin group selected from the group consisting of a chemical toxin, a single chain toxin, and a modified toxin having an intrinsic toxic group lacking a functional binding domain, said conjugate selectively binding to a gonadotroph and substantially precluding said gonadotroph from secreting gonadotropins, said method comprising administering an effective amount of said conjugate to said animal to substantially preclude secretion of gonadotropins by said animal's gonadotrophs, wherein said conjugate the cell membrane of a gonadotroph and wherein said peptide hormone has the general formula pyroGlu-His-Trp-Ser-Tyr-X-Leu-Arg-Pro, wherein X is an amino acid selected from the group consisting of lysine, D-lysine, ornithine, D-ornithine, glutamic avid, D-glutaniic acid, aspartic acid, D-aspartic acid, cysteine, D-cysteine, tyrosine and D-tyrosine.