Abstract
Two types of binding sites have previously been described for 36-amino acid neuropeptide Y (NPY), called Y1 and Y2 receptors. Y2 receptors can bind long C-terminal fragments of NPY-e.g., NPY-(13-36)-peptide. In contrast, Y1 receptors have until now only been characterized as NPY receptors that do not bind such fragments. In the present study an NPY analog is presented, [Leu31, Pro34]NPY, which in a series of human neuroblastoma cell lines and on rat PC-12 cells can displace radiolabeled NPY only from cells that express Y1 receptors and not from those expressing Y2 receptors. The radiolabeled analog, [125I-Tyr36] monoiodo-[Leu31, Pro34]NPY, also binds specifically only to cells with Y1 receptors. The binding of this analog to Y1 receptors on human neuroblastoma cells is associated with a transient increase in cytoplasmic free calcium concentrations similar to the response observed with NPY. [Leu31, Pro34]NPY is also active in vivo as it is even more potent than NPY in increasing blood pressure in anesthetized rats. It is concluded that [Leu31, Pro34]NPY is a specific Y1 receptor agonist and that the analog or variants of it can be useful in delineating the physiological importance of Y1 receptors.
| Originalsprog | Engelsk |
|---|---|
| Tidsskrift | Proceedings of the National Academy of Sciences of the United States of America |
| Vol/bind | 87 |
| Udgave nummer | 1 |
| Sider (fra-til) | 182-6 |
| Antal sider | 5 |
| ISSN | 0027-8424 |
| Status | Udgivet - 1990 |