Radioligand binding experiments were performed with crude homogenates from normal human skin in order to investigate substance P receptor density. Binding of [3H]substance P ([3H]SP) reached equilibrium after 20 min and was saturable analysis of saturation curves gave a significantly better fit using two-site binding compared to the single-site model. Competition studies employing some selective agonists for NK1, NK2 and NK3 receptors have demonstrated that only the NK1 selective agonist, [Sar9, Met(O2)11]-SP, was a competitor for [3H]SP binding. In addition, the non-hydrolyzable guanosine 5'-0-(3-thiotriphosphate) altered the dissociation of SP from NK1 receptors by increasing the number of low-affinity sites. These data show that in the skin [3H]SP binds to a single population of substance P high-affinity sites, which represent NK1-type receptors.
Titolo: | Characterization of [3H]substance P binding sites in human skin. |
Autori di Ateneo: | |
Autori: | BIANCHI, BEATRICE; MATUCCI, ROSANNA; A. Danesi; R. Rossi; P. Ipponi; GIANNOTTI, BENVENUTO; O. Johansson; CAPPUGI, PIETRO |
Data di pubblicazione: | 1999 |
Rivista: | |
Volume: | 12 |
Pagina iniziale: | 6 |
Pagina finale: | 10 |
Abstract: | Radioligand binding experiments were performed with crude homogenates from normal human skin in order to investigate substance P receptor density. Binding of [3H]substance P ([3H]SP) reached equilibrium after 20 min and was saturable analysis of saturation curves gave a significantly better fit using two-site binding compared to the single-site model. Competition studies employing some selective agonists for NK1, NK2 and NK3 receptors have demonstrated that only the NK1 selective agonist, [Sar9, Met(O2)11]-SP, was a competitor for [3H]SP binding. In addition, the non-hydrolyzable guanosine 5'-0-(3-thiotriphosphate) altered the dissociation of SP from NK1 receptors by increasing the number of low-affinity sites. These data show that in the skin [3H]SP binds to a single population of substance P high-affinity sites, which represent NK1-type receptors. |
Handle: | http://hdl.handle.net/2158/346040 |
Appare nelle tipologie: | 1a - Articolo su rivista |