title: Nitric oxide synthase immunoreactivity and NADPH-d histochemistry in the enteric nervous system of Sarda breed sheep with different PrP genotypes in whole-mount and cryostat preparations.
abstract: Until now, significant differences in the neurochemical pattern of enteric neurons have been demonstrated in all species studied; however, some strong similarities also occur across species, such as the occurrence of nitric oxide synthase immunoreactivity (NOS-IR) in inhibitory motor neurons to muscle. In consideration of the insufficient data regarding the enteric nervous system (ENS) of sheep, we investigated the myenteric plexus and submucosal plexus of the ovine ileum. Since the pivotal role of the ENS in the early pathogenesis of sheep scrapie, the "prototype" of prion diseases, has been suggested, we have focused our observations also on the host's PrP genotype. We have studied the morphology and distribution of NOS-IR neurons and their relationships with the enteric glia in whole-mount preparations and in cryostat sections. NOS-IR neurons, always encircled by glial processes, were located in both plexuses. Many NOS-IR fibers were seen in the circular muscle layer, in the submucosa, and in the mucosa. In the submucosa they were close to the lymphoid tissue. No differences in the distribution and percentage of NOS-IR fibers and neurons were observed among sheep carrying different PrP genotype, thus making unlikely their contribution in the determinism of susceptibility/resistance to scrapie infection.
authors.affiliation: Department of Veterinary Morphophysiology and Animal Productions, University of Bologna, Bologna, Italy. lalatta@vet.unibo.it
authors.forename: Giovanna
authors.initials: G
authors.lastname: Lalatta-Costerbosa
authors.forename: Maurizio
authors.initials: M
authors.lastname: Mazzoni
authors.forename: Paolo
authors.initials: P
authors.lastname: Clavenzani
authors.forename: Giovanni
authors.initials: G
authors.lastname: Di Guardo
authors.forename: Gemma
authors.initials: G
authors.lastname: Mazzuoli
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Marruchella
authors.forename: Luigi
authors.initials: L
authors.lastname: De Grossi
authors.forename: Umberto
authors.initials: U
authors.lastname: Agrimi
authors.forename: Roberto
authors.initials: R
authors.lastname: Chiocchetti
mesh_terms: D000818:Animals; D016616:Cryoultramicrotomy / Q000379:methods; D017615:Enteric Nervous System / Q000201:enzymology*; D005260:Female; D005838:Genotype; D007150:Immunohistochemistry; D008856:Microscopy, Fluorescence; D009252:NADPH Dehydrogenase / Q000032:analysis*; D009474:Neurons / Q000201:enzymology; D019001:Nitric Oxide Synthase / Q000032:analysis*; D018620:PrPSc Proteins / Q000235:genetics*; D012756:Sheep / Q000235:genetics / Q000378:metabolism*
chemical_list: D018620:PrPSc Proteins; D019001:Nitric Oxide Synthase; D009252:NADPH Dehydrogenase