Response of the gut neuroendocrine system of Leuciscus cephalus (L.) to the presence of Pomphorhynchus laevis Müller, 1776 (Acanthocephala)
G. Bosi1, C. Domeneghini1, S. Arrighi1, L. Giari2, E. Simoni2 and B.S. Dezfuli2
1Department of Veterinary Sciences and Technologies for Food Safety, Milan, Italy and 2Department of Biology, University of Ferrara, Ferrara, Italy
Offprint requests to: Bahram S. Dezfuli, Department of Biology, University of Ferrara, Via Borsari, 46, 44100 Ferrara, Italy. e-mail: dzb@unife.it
Summary. Immunohistochemical tests were applied to sections of intestine of uninfected and Pomphorhynchus laevis Müller-infected chub, Leuciscus cephalus (L.) using 15 different antisera. Nerve cell bodies and fibres immunoreactive (IR) to the anti-bombesin, -Cholecystokinin-8 (CCK-8), -galanin, -Gastrin-Releasing Peptide (-GRP), -Nitric Oxide Synthase (-NOS), -Substance P (-SP), and -Vasoactive Intestinal Peptide (-VIP) sera were observed in the myenteric plexus of uninfected chub. The density of nerve components immunoreactive to these antisera was high in the intestine of the infected fish, especially near the site of attachment. Moreover, numerous nerve fibres, immunoreactive to anti-bombesin, -GRP, -galanin, -SP, and -VIP sera, were encountered in the connective tissue capsule surrounding the bulb and proboscis of P. laevis. The occurrence of P. laevis in the chub gut significantly increased the number of endocrine cells per intestinal fold immunoreactive to galanin, met-enkephalin and leu-enkephalin antisera. CCK-8, Neuropeptide Y and glucagon-like immunoreactive cells were less numerous in the intestine of infected chub. A large number of cells in the tunica propria-submucosa of L. cephalus infected with P. laevis were immunoreactive to anti-serotonin and -leu-enkephalin sera. Histol Histopathol 20, 509-518 (2005).
Key words: Immunohistochemistry, Neuroendocrine system, Digestive tract, Leuciscus cephalus, Acanthocephalan infection
DOI: 10.14670/HH-20.509