Morfologia ed espressione neurochimica dei neuroni immunoreattivi per il peptide correlato al gene della calcitonina (CGRP-IR) nell'ileo di agnello

The CGRP was localized immunohistochemically in neurons and fibres in lamb ileum wholemount preparations and cryostat sections. The neurochemical coding of CGRP-IR neurons in both the plexuses was also investigated. In wholemounts the immunoreactivity was observed only in well-defined Dogiel type II neurons. In the myenteric plexus and submucosal plexus neurons the CGRP-IR was co-localised only with TK-IR; no CGRP-IR neurons exhibited VIP-, NOS-, and TH-IR. In cryostat sections a dense network of CGRP-IR fibres was mainly observed in the lamina propria beneath the epithelium basal membrane and around the lacteals, in the lateral walls of the follicular sinuses, around the lymphatic follicles (Peyer’s platches), and along enteric vessels. Rare CGRP-IR fibres were present in the muscular layers.