The non-peptide neuropeptide Y Y1 receptor antagonist BIBP3226 blocks the [Leu31,Pro34]neuropeptide Y-induced modulation of alpha 2-adrenoceptors in the nucleus tractus solitarii of the rat

• Published in: Neuroreport Vol. 7; no. 15-17; p. 2701
• Main Authors: Yang, S N, Finnman, U B, Fuxe, K
• Format: Journal Article
• Language: English
• Published: England 04.11.1996
• Subjects: Animals; Arginine - analogs & derivatives; Arginine - pharmacology; Dose-Response Relationship, Drug; Male; Rats; Rats, Sprague-Dawley; Receptors, Adrenergic, alpha-2 - drug effects; Receptors, Neuropeptide Y - antagonists & inhibitors; Solitary Nucleus - drug effects
• ISSN: 0959-4965
• DOI: 10.1097/00001756-199611040-00059

The potential blockade of the neuropeptide Y (NPY) Y1 receptor agonist [Leu31,Pro34]NPY-induced modulation of the characteristics of alpha 2-adrenoceptor agonist [3H]p-aminoclonidine binding sites by a selective non-peptide NPY Y1 receptor antagonist BIBP3226, was studied in the nucleus tractus solitarii of the rat by means of quantitative receptor autoradiography. [Leu31,Pro34]NPY at a concentration of 10 nM significantly increased the Kd value of [3H]p-aminoclonidine binding sites in the nucleus tractus solitarii without influencing the Bmax, suggesting the existence of an antagonistic modulation by NPY Y1 receptors of alpha 2-adrenoceptors in the nucleus tractus solitarii. BIBP3226 at 100 nM fully blocked the [Leu31,Pro34]NPY-induced increase in Kd of the [3H]p-aminoclonidine binding sites. The present results therefore provide evidence, by use of a NPY Y1 receptor antagonist, for the existence of a NPY Y1/alpha 2 receptor interaction in the nucleus tractus solitarii.