Selective agonists of NK-2 binding sites highly active on rat portal vein (NK-3 bioassay)

Neuropeptides. 1991 Jun;19(2):91-5. doi: 10.1016/0143-4179(91)90137-8.

Abstract

All the synthetized NKA and NKA (4-10) agonists have been found active in the rat portal vein bioassay. Even [Lys5, MeLeu9, Nle10] NKA(4-10), a highly potent competitor of NK-2 binding sites with very low binding potencies for NK-1 and NK-3 sites (IC50 greater than microM) is still active in contracting the rat portal vein. These results suggest that this tissue contains not only a fairly large population of NK-3 receptors but also a minor population of NK-2 receptors. Comparison of the activities of NKA C-terminal analogues on the guinea-pig ileum suggests that 1) only a small population of NK-2 receptors are present in this tissue and 2) beside NK-1, NK-2 and NK-3 receptors, another type of receptor sensitive to C-terminal sequences might be present in the guinea-pig tissue.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Biological Assay
  • Guinea Pigs
  • Molecular Sequence Data
  • Neurokinin A / metabolism*
  • Neurokinin B / metabolism
  • Peptide Fragments / metabolism*
  • Portal Vein / chemistry*
  • Portal Vein / metabolism
  • Rabbits
  • Radioimmunoassay
  • Rats
  • Receptors, Neurokinin-2
  • Receptors, Neurokinin-3
  • Receptors, Neurotransmitter / analysis*
  • Receptors, Neurotransmitter / metabolism
  • Receptors, Tachykinin
  • Structure-Activity Relationship
  • Tachykinins / metabolism*
  • Tachykinins / pharmacology

Substances

  • Peptide Fragments
  • Receptors, Neurokinin-2
  • Receptors, Neurokinin-3
  • Receptors, Neurotransmitter
  • Receptors, Tachykinin
  • Tachykinins
  • Neurokinin A
  • Neurokinin B
  • neurokinin A(4-10)
  • neurokinin B (4-10)