Distribution and chemical coding of corticotropin-releasing factor-immunoreactive neurons in the guinea pig enteric nervous system

• Published in: Journal of comparative neurology (1911) Vol. 494; no. 1; pp. 63 - 74
• Main Authors: Liu, Sumei, Gao, Na, Hu, Hong-Zhen, Wang, Xiyu, Wang, Guo-Du, Fang, Xiucai, Gao, Xiang, Xia, Yun, Wood, Jackie D.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.01.2006
• Subjects: Animals; Calbindin 2; Calbindins; Calcitonin Gene-Related Peptide - metabolism; Cell Count - methods; Choline O-Acetyltransferase - metabolism; Colchicine - pharmacology; Corticotropin-Releasing Hormone - metabolism; ELAV Proteins - metabolism; Enteric Nervous System - cytology; gastrointestinal tract; Guinea Pigs; Immunohistochemistry - methods; In Vitro Techniques; Male; myenteric plexus; Myenteric Plexus - cytology; Myenteric Plexus - drug effects; Myenteric Plexus - metabolism; Neurons - chemistry; Neurons - metabolism; Neuropeptide Y - metabolism; Nitric Oxide Synthase - metabolism; Phosphopyruvate Hydratase - metabolism; Pyloric Antrum - cytology; Pyloric Antrum - drug effects; Pyloric Antrum - metabolism; Receptors, Corticotropin-Releasing Hormone - metabolism; S100 Calcium Binding Protein G - metabolism; Serotonin - metabolism; Somatostatin - metabolism; stress; submucosal plexus; Substance P - metabolism; Tyrosine 3-Monooxygenase - metabolism; Urocortins; Vasoactive Intestinal Peptide - metabolism
• ISSN: 0021-9967; 1096-9861
• DOI: 10.1002/cne.20781

Immunofluorescence was used to study immunoreactivity (IR) for corticotropin‐releasing factor (CRF) in the guinea pig enteric nervous system. CRF‐IR was expressed in both the myenteric and the submucosal plexuses of all regions of the large and small intestine and the myenteric plexus of the stomach. CRF‐IR nerve fibers were present in the myenteric and submucosal plexuses, in the circular muscle coat, and surrounding submucosal arterioles. Most of the CRF‐IR fibers persisted in the myenteric and submucosal plexuses after 7 days in organotypic culture. CRF‐IR was not coexpressed with tyrosine hydroxylase‐IR or calcitonin gene‐related peptide‐IR fibers. The proportions of CRF‐IR cell bodies in the myenteric plexus increased progressively from the stomach (0.6%) to the distal colon (2.8%). Most of the CRF‐IR myenteric neurons (95%) had uniaxonal morphology; the remainder had Dogiel type II multipolar morphology. CRF‐IR cell bodies in the myenteric plexus of the ileum expressed IR for choline acetyltransferase (56.9%), substance P (55.0%), and nitric oxide synthase (37.9%). CRF‐IR never colocalized with IR for calbindin, calretinin, neuropeptide Y, serotonin, or somatostatin in the myenteric plexus. CRF‐IR cell bodies were more abundant in the submucosal plexus (29.9–38.0%) than in the myenteric plexus. All CRF‐IR neurons in submucosal ganglia expressed vasoactive intestinal peptide‐IR and were likely to be secretomotor/vasodilator neurons. CRF‐IR neurons did not express IR for the CRF1 receptor. CRF1‐IR was expressed in neuronal neighbors of those with CRF‐IR. Collective evidence suggests that VIPergic secretomotor neurons might provide synaptic input to neighboring cholinergic neurons. J. Comp. Neurol. 494:63–74, 2006. © 2005 Wiley‐Liss, Inc.