Badgery-Parker T, Zeng X P, Lavielle S, Burcher E
School of Physiology and Pharmacology, University of New South Wales, Sydney, Australia.
Regul Pept. 1993 Jul 2;46(1-2):455-7. doi: 10.1016/0167-0115(93)90118-r.
A new radioligand, [125I]-[Lys5,Tyr(I2)7,MeLeu9,Nle10]-NKA(4-10), based on the selective agonist [Lys5,MeLeu9,Nle10]-NKA(4-10) has been developed. Binding in rat fundus membranes was displaced by NP gamma > NKA > or = [Lys5,MeLeu9,Nle10]-NK(4-10) > neuropeptide K > [Lys5,Tyr(I2)7,MeLeu9,Nle10]-NKA(4-10) > SP > [Sar9,Met(O2)11]-SP >> senktide, indicating binding to NK-2 receptors. Preliminary studies demonstrated high specific binding in membranes from rat urinary bladder, duodenum and colon. Specific binding in rat brain and lung was negligible, and binding in a range of guinea-pig tissues was no more than 35% specific. These data may indicate species differences in NK-2 receptors.
