Morphology of the digestive gland of the marine panpulmonate limpet Siphonaria lessonii: A cytological, histochemical, and ultrastructural description. (17th July 2019)

• Record Type: Journal Article
• Authors: Landro, Sonia M.; Teso, Valeria; Arrighetti, Florencia
• Is Part Of: Journal of morphology. Volume 280:Number 10(2019)
• Page Start: 1475
• Page End: 1484
• Publication Date: 2019-07-17
• Subjects: cell types -- digestive gland -- histochemistry -- Siphonariidae; Morphology -- Periodicals; Physiology -- Periodicals; Anatomy -- Periodicals; 571.3
• DOI: 10.1002/jmor.21043
• Languages: English
• ISSNs: 0362-2525

Abstract

Abstract: The molluskan digestive gland has been widely studied and its structural and ultrastructural descriptions have allowed the understanding of its several functions. Despite siphonarids are broadly distributed around the world, morphological studies on their digestive system are poorly represented. The panpulmonate limpet Siphonaria lessonii is the most abundant gastropod and the dominant herbivore in the rocky intertidal coast of Buenos Aires. The aim of this study was to describe the morphology, histology, ultrastructure, and histochemistry of the digestive gland of this gastropod as well as the cycle of activity of digestion. For that, different histochemical techniques along with light microscopy, transmission electron microscopy, and scanning electron microscopy were employed. This study revealed a complex epithelium, composed of a simple layer with five cell types. Digestive cells and vacuolated cells are responsible for intracellular digestion and energy accumulation; basophilic cells, secrete substances that would be involved in extracellular digestion; pigmented cells might have an excretory function and thin cells would correspond to undifferentiated cells. In addition, the tubules present a changing morphology according to the digestive activity that they undergo. As S. lessonii is a grazer that feeds continuously, the cycle of activity of the digestive gland seems to be daily. Abstract : The digestive gland of Siphonaria lessonii is brownish and globular, and it is located in the posterior zone of the animal in close contact with the hermaphrodite gonad. It is formed by blind‐ended tubules whose epithelium is composed of a simple layer with five cell types: digestive, basophilic, vacuolated and pigmented, observed under light microscopy and thin cells only observed under transmission electron microscopy. The tubules present a changing morphology according to the digestive activity that they undergo.