Novel Chimeric Analgesic Peptides

Abstract

The present invention provides a novel chimeric peptide containing an opioid peptide moiety and a nociceptive peptide moiety for producing analgesia.

1 - 23 . (canceled) 
     
     
         24 . A method for treating pain in a mammal, said method comprising administering to said mammal a chimeric peptide comprising an agonist opioid receptor binding moiety at its N-terminus and an agonist Substance P receptor binding moiety at its C-terminus, in an amount sufficient to induce analgesia in said mammal. 
     
     
         25 . The method of  claim 24  wherein, in the peptide, the agonist opioid receptor binding moiety is μ, δ or κ agonist opioid receptor binding moiety. 
     
     
         26 . The method of  claim 25  wherein, in the peptide, the agonist opioid receptor binding moiety is a μ agonist opioid receptor binding moiety. 
     
     
         27 . The method of  claim 26  wherein, in the peptide, the N-terminal amino acid residue of said opioid receptor binding moiety is a free amine. 
     
     
         28 . The method of  claim 27  wherein, in the peptide, the N-terminal amino acid residue of said opioid receptor binding moiety is Tyr. 
     
     
         29 . The method of  claim 28  wherein, in the peptide, said opioid receptor binding moiety is a peptide having any one of SEQ ID Nos: 1-11, or N-terminal fragment thereof. 
     
     
         30 . The method of  claim 28  wherein, in the peptide, said opioid receptor binding moiety is endomorphin 1, endomorphin 2, or N-terminal fragment thereof. 
     
     
         31 . The method of  claim 30  wherein, in the peptide, said opioid receptor binding moiety is a peptide having SEQ ID No: 2 or 3, or N-terminal fragment thereof. 
     
     
         32 . The method of  claim 26  wherein, in the peptide, said agonist Substance P receptor binding moiety comprises Substance P, or C-terminal Substance P fragment thereof. 
     
     
         33 . The method of  claim 26  wherein, in the peptide, the —COOH moiety of the C-terminal amino acid residue of said Substance P receptor binding moiety is protected. 
     
     
         34 . The method of  claim 33  wherein, in the peptide, the —COOH moiety of the C-terminal amino acid residue of said Substance P receptor binding moiety is amidated. 
     
     
         35 . The method of  claim 34  wherein, in the peptide, the C-terminal amino acid residue of said Substance P receptor binding moiety is Met-NH 2 . 
     
     
         36 . The method of  claim 35  wherein, in the peptide, said Substance P receptor binding moiety is a peptide having any one of SEQ ID Nos: 21, 36 and 38-41, or C-terminal fragment thereof. 
     
     
         37 . The method of  claim 26  wherein, in the peptide, the opioid receptor binding moiety is endomorphin 1, endomorphin 2, or N-terminal fragment thereof; and the Substance P receptor binding moiety is Substance P, or C-terminal fragment thereof. 
     
     
         38 . The method of  claim 26  wherein the peptide has SEQ ID No: 42. 
     
     
         39 . The method of  claim 26  wherein the peptide has SEQ ID No: 43. 
     
     
         40 . The method of  claim 24  wherein the method of administration is selected from the group consisting of intrathecal, intracerebroventricular and systemic administration. 
     
     
         41 . The method of  claim 24  wherein the peptide is administered with a solubilizing agent. 
     
     
         42 . The method of  claim 41  wherein the solubilizing agent is cyclodextran.