Functional Morphology of the Salivary Gland of the Snail, Helix Pomatia: A Histochemical and Immunocytochemical Study
Abstract
Functional morphology of Helix pomatia salivary gland cells was studied at light microscopic level by using different histochemical methods. Three cell types could be demonstrated in the salivary gland: mucocytes, granular and vacuolated cells. The distribution and the number of the different cell types were different in active and inactive snails. In active feeding animals, dilatated interlobular salivary ducts were observed, which were never present in inactive ones. In active animals an additional cell type, the cystic cell could also be observed. Periodic acid Schiff staining revealed both mucuos and serous elements in the salivary gland. Furthermore, hematoxyline-eosin staining indicated the occurrence of a cell layer with high mitotic activity in the acini. Applying immunohistochemical methods with monoclonal mouse anti-human Ki-67 clone, B56 and polyclonal rabbit anti-human Ki-67 antibodies, we also were able to demonstrate the occurrence of dividing cells in the salivary gland. Analysis of 1–2 um semi-thin Araldite sections stained with toluidine-blue showed that the saliva can be released, in addition to possible exo-cytosis, by the lysis of cystic cells. Using an apoptosis kit, we could also establish that this process was due to rather an apoptotic than a necrotic mechanism. In the salivary gland of active snails, where an intensive salivation takes place, significantly more apoptotic cells occurred, if compared to that of inactive animals. It is suggested that programmed cell death may also be involved in the saliva release.
Keywords
Salivary gland cystic cell dividing cell apoptosis snailReferences
- 1.Bani, G., Formigli, L., Cecchi, R. (1990) Morphological study on the salivary glands of Eobania ver-miculata (Miiller) (Mollusca, Pulmonata). Z. mikrosk.-anat. Forsch. Leipzig. 104, 856–870.Google Scholar
- 2.Beltz, B., Gelperin, A. (1979) An ultrastructural analysis of the salivary system of the terrestrial mollusc, Limax maximus. Tissue and Cell 11, 31–50.CrossRefGoogle Scholar
- 3.Boer, H. H., Bonga, S. E. W., van Rooyen, N. (1967) Light and electron microscopical investigations on the salivary glands of Lymnaea stagnalis L. Zeitschrift fur Zellforschung. 76, 228–247.CrossRefGoogle Scholar
- 4.Charrier, Y. M. (1988) Structure des glandes salivaries d’Helix aspersa Miiller (Mollusque, Gasteropode, Pulmone). Haliotis, 18, 171–173.Google Scholar
- 5.Elekes, K., Ude, J. (1994) Peripheral Connections of FMRFamide-immunreactive neurons in the snail, Helixpomatia. An immunogold electronmicroscopic study. J. Neurocytology 23, 758–769.CrossRefGoogle Scholar
- 6.Elekes, K. (2000) Ultrastructural aspects of peptidergic modulation in the peripoheral nervous system of Helix pomatia. Micros. Res. Tech. 49, 534–546.CrossRefGoogle Scholar
- 7.Farber, E. (1994) Programmed cell death: necrosis versus apoptosis. Mod. Pathol. 7, 605–609.Google Scholar
- 8.Kiss, T., Hiripi, L., Papp, N., Elekes, K. (2003) Dopamine and serotonin receptors mediating contractions of the snail, Helix pomatia, salivary duct. Neuroscience 116, 755–790.CrossRefGoogle Scholar
- 9.Krijgsman, B. S. (1928) Arbeitsrythmus der Verdauungsdriisen bei Helix pomatia. Z. vergl. Physiol. 8, 425–658.CrossRefGoogle Scholar
- 10.Lim, C.-S., Lee, J.-C., S. D., Chang, D.-J., Kaang, B.-K. (2002) Hydrogen peroxide-induced cell death in cultured Aplysia sensory neurons. Brain Res. 941, 137–145.CrossRefGoogle Scholar
- 11.Lobo-da-Cunha, A. (2001) Ultrastructural and histochemical study of the salivary glands of Aplysia depilans (Mollusca, Opisthobranchia). Acta Zoologica 82, 201–212.Google Scholar
- 12.Luchtel, D. L., Martin, A. W., Deyrup-Olsen, I., Boer, H. H. (1997) Gastropoda: Pulmonata. Microscopic Anatomy of Invertebrates 6B: Mollusca II, Wiley-Liss, Inc. New York.Google Scholar
- 13.Moreno, F. J., Pinero, J., Hidalgo, J., Navas, P., Aijon, J., Lopez-Campos, J. L. (1982) Histochemical and ultrastructural studies on the salivary glands of Helix aspersa (Mollusca). J. Zool, Lond. 196, 343–354.CrossRefGoogle Scholar
- 14.Moya, J., Serrano, M. T., Angulo, E. (1992) Ultrastructure of the salivary glands oiArion ater (gastropoda, pulmonata). Biological Structures and Morphogenesis, 4, 81–87.Google Scholar
- 15.Pacaut, M., Vigier, P. (1906) Les glandes salivaries de l’escargot. Arch. Anat. micr. Morph. exp. 8, 425–658.Google Scholar
- 16.Quattrini, D. (1967) Osservazioni sulla ultrastruttura dei dotti escretori delle ghiandole salivari di Helix aspersa Miiller (Mollusca, Gastropoda, Pulmonata). Caryologia, 20, 191–206.CrossRefGoogle Scholar
- 17.Serrano, T., Gomez, B. J., Angulo, E. (1996) Light and electron microscopy study of the salivary gland secretory cells of Helicoidea (Gastropoda, Stylommatophora). Tissue & Cell 28, 237–251.CrossRefGoogle Scholar
- 18.Vaux, D. L., Strasser, A. (1996) The molecular biology of apoptosis. Proc. Natl. Acad. Sci. USA, 93, 2239–2244.CrossRefGoogle Scholar
- 19.Walker, G. (1970) Light and electron microscope investigations on the salivary glands of the slug, Agriolimax reticulatus (Miiller). Protoplasma 71, 111–126.CrossRefGoogle Scholar
Copyright information
This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.