Histological Study of Gonadogenesis in Potamopyrgus Antipodarum and Valvata Piscinalis
Résumé
This study focuses on gonad development in two freshwater gastropod prosobranch snail species (Potamopyrgus antipodarum and Valvata piscinalis). These biological models have been shown to be sensitive to various reprotoxic substances and are known to be relevant organisms for studying endocrine-disrupting substances. Therefore we took up a histological study of their anatomy and the gametogenesis of the two species in order to key into biological elements potentially useful for reprotoxic stress studies. Knowing that P. antipodarum is parthenogenetic, we studied all their gonadogenetic stages, taking caution to clearly describe the different oocyte developmental stages leading to the formation of the copulatory bursa, characterizing neighboring glands. As for V. piscinalis, a hermaphrodite species, all the spermatogenesis development stages were described (spermatocytogenesis and spermiogenesis) as well as specification of nourishing cells and support cells, the objective being to define the species' reproduction mechanism. This studied was carried out by observing the development of young P. antipodarum and V. picinalis, exposing them to the same experimental conditions for 6 months. Weekly samples were taken for biometric imaging and conventional histology photonics in order to determine the age and to validate the appearance of early gonadogenesis. A fundamental, detailed study on tissue identification was conducted to accomplish this task.
Mots clés
Early gametogenesis Leydig cells Sertoli cells Germinal cells Mitosis division Meiotic division Albumen gland Ovogonium Ovocyte Spermatogenesis Vitellogenesis
Early gametogenesis
Leydig cells
Sertoli cells
Germinal cells
Mitosis division
Meiotic division
Albumen gland
Ovogonium
Ovocyte
Spermatogenesis
Vitellogenesis
Domaines
Sciences de l'environnement
Origine : Fichiers éditeurs autorisés sur une archive ouverte