The invention provides a novel amino acid, neo-tryptophan, as well as polypeptides containing this novel amino acid such as neurotensin analogs. In addition, the invention provides neo-tryptophan derivatives, serotonin-like neo-tryptophan derivatives, and polypeptides containing such derivatives. The invention also provides methods for making neo-tryptophan, neo-tryptophan derivatives, serotonin-like neo-tryptophan derivatives, and compositions containing these compounds. Further, the invention provides methods for inducing a neurotensin response in a mammal as well as methods for treating a mammal having a serotonin recognition molecule.
1. A method of inducing antinociception in a human, said method comprising administering an effective dose of a polypeptide comprising neo-tryptophan to the human.
2. The method of claim 1 , wherein the polypeptide is a neurotensin analog.
3. The method of claim 2 , wherein the neo-tryptophan is located at position 11 of neurotensin.
4. The method of claim 1 , wherein the polypeptide is selected from the group consisting of NT64D, NT64L, NT65L, NT66D, NT66L, NT67L, NT69L, NT69L′, NT71, NT72, NT73, NT74, NT75, NT76, and NT77.
5. The method of claim 1 , wherein the polypeptide comprises an L-neo-tryptophan.
6. The method of claim 1 , wherein the polypeptide comprises a D-neo-tryptophan.
7. The method of claim 1 , wherein the administration is extracranial.
8. The method of claim 1 , wherein the administration is intraperitoneal, intravenous, intradermal, subcutaneous, oral, or nasal administration.