Qualitative and quantitative analysis of tachykinin NK2 receptors in chemically defined human colonic neuronal pathways

摘要: The involvement of NK2 receptors (NK2r) in the neuroregulation human colonic motility has been mainly assessed by using pharmacological approaches. aim this study was to characterize intramural neurons and nerve varicosities expressing NK2r neuronal pathways. Neuronal coding myenteric plexus external muscle layers identified on basis patterns colocalization tachykinins (TK), vesicular acetylcholine transporter (VAChT), nitric oxide synthase (NOS), glutamate decarboxylase (GAD), vasoactive intestinal peptide (VIP) with immunoreactivity. proportions chemically defined synaptophysin-immunoreactive were accurately determined specific software. immunoreactivity detected soma many (71.8%). A large proportion these immunoreactive VAChT (39.3%), TK (30%), GAD (23.5%) and, a lesser extent, NOS VIP. showed significant regional differences: highest (59.8%) located plexus. High VIP (80.9%) (77.9%), lower recorded VAChT, TK, GAD. In circular longitudinal layers, 49.6% 45.3%, respectively. intramuscular closely apposed smooth cells NK2r. conclusion, data obtained study, which expression mapped pathways, confirm that are involved neuroneuronal neuromuscular processes regulating motility. J. Comp. Neurol. 507:1542–1558, 2008. © 2008 Wiley-Liss, Inc.