Ganglionar nervous cells and telocytes in the pancreas of Octodon degus Extra and intrapancreatic ganglionar cells and telocytes in the degus Cleofina Bosco ⁎, Eugenia Díaz, Rodrigo Gutiérrez, Jaime González, Johanna Pérez Programa de Anatomía y Biología del Desarrollo, ICBM, Facultad de Medicina, Universidad de Chile, Chile abstract article info Article history: Received 27 December 2012 Received in revised form 2 May 2013 Accepted 4 May 2013 Keywords: Octodon degus Caviomorph rodent Pancreas Ganglionar nervous cells Enteric nervous system Telocytes This study shows for the first time the presence of intra and extrapancreatic ganglionar neurons and telocytes in Octodon degus such as those described in human and guinea pig pancreas. Pancreatic ganglionar neurons were identified by their histological characteristics as well as their positive immunostaining with mouse anti-human neuron specific enolase (NSE) antibody. Somatostatin secreting delta cells (D cells) in the islets of Langerhans were identified by positive immunostaining with rabbit antihuman polyclonal somatostatin antibody. Electron microscopy evidenced the presence of some unmyelinated axons in the interlobular spaces or septa, usually located adjacent to blood vessels and the exocrine epithelial ducts. The presence of telocytes with at least 2 telopodes was observed in the interlobular space, frequently in close spatial relation- ship with blood vessels and nerve endings. Telocytes were often observed in the vicinity or even in close proximity with both secretory acini and exocrine epithelial ducts and regulatory nerves and blood vessel ap- paratuses. A possible framework has been put forward within which such structures might contribute to elic- it physiological responses in the pancreas. Further studies of synaptic interactions within and between pancreatic neuron cells are needed to help clarify the morphological results reported here. A broad overview of the field of neurogastroenterology with focus on the pancreas of O. degus related to the enteric nervous system (ENS) is provided in order to help design future studies on the connections of specific neurons forming pancreatic pathways, their neurotransmission processes and how disruption of these pathways may contribute to pancreatic disease. © 2013 Elsevier B.V. All rights reserved. 1. Introduction Octodon degus (degus) is a small diurnal caviomorph rodent native to Chile. The gestation period lasts 90 days and the average litter size is five pups. This animal adapts easily to animal facility conditions and has been used as an experimental model in a variety of studies re- garding subjects such as placenta (Bosco, 1997; Bosco et al., 2007; Kertschanska et al., 1997; King, 1992), toxicology (Bosco, 2005; Bosco et al., 1997), diabetic eye cataract development (Nishi and Steiner, 1990), circadian rhythms (Lee, 2004), Alzheimer's disease (Inestrosa et al., 2005) and visual organization (Jacobs et al., 2003). The degus has ordinary and high circulating glucose levels (Opazo et al., 2004), and its endocrine pancreas has unique alpha-cell crystals, a herpes-like virus, and islet amyloidosis (Spear et al, 1984). The molecular biochemistry of pancreatic hormones in degus (Hellman et al., 1990) and guinea pig (Iturriza et al., 1995) related to beta and alpha cells has been widely analyzed. Clear analogies, such as failure to stain alpha-cells using antisera against the C-terminal portions of the glucagon molecule, have been described for these two caviomorph species. Additionally, some studies have also demonstrated a number of morphological and struc- tural similarities between other organs of these species, especially re- garding the placenta (Bosco, 1997; Bosco et al., 2007; Mess et al., 2007; Valdés et al., 2008). The morphology, neurochemistry and electrical properties of guinea pig pancreatic neurons have been described by Liu and Kirchgessner (1997). Although their role in the physiology of exocrine and endocrine secretion is still under study, according to these authors pancreatic ganglia should not be regarded as a simple relay ganglia interposed be- tween the vagus nerve and the effector organs. Indeed, the pancreatic ganglia are much more complex, and it is thought that because of this complexity, the pancreas displays a degree of independence when cut off from the brain, spinal cord, or gut (Stagner and Samols, 1985). Fur- thermore, the observation of spontaneous activity within connected pancreatic ganglia gives support to the idea of an endogenous neural network regulating pancreatic function (Liu and Kirchgessner, 1997). The aim of this study was to acquire information regarding the mor- phology of ganglionar neurons in the degus pancreas in order to com- pare them to those described in the guinea pig (Kirchgessner and Pintar, 1991; Liu et al., 1996), to further our understanding of the func- tion of this organ under normal and pathological conditions. Autonomic Neuroscience: Basic and Clinical 177 (2013) 224–230 ⁎ Corresponding author at: Laboratorio de Placenta y Reproducción, ICBM, Programa de Anatomía y Biología del Desarrollo, Facultad de Medicina, Universidad de Chile, Independencia 1027, Casilla 70079, Santiago 7, Chile. Tel.: +56 2 6786783; fax: +56 2 6786264. E-mail address: cbosco@med.uchile.cl (C. Bosco). 1566-0702/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.autneu.2013.05.002 Contents lists available at ScienceDirect Autonomic Neuroscience: Basic and Clinical journal homepage: www.elsevier.com/locate/autneu