Esra Akat

Histochemical and Biometric Study of the Gastrointestinal System of Hyla Orientalis (Bedriaga, 1890) (Anura, Hylidae)

This study was carried out to assess the localization of hyaluronic acid (HA) and the distribution of glycoproteins in the gastrointestinal system of adult Hyla orientalis. Histochemical analysis of the gastrointestinal system in H. orientalis showed that mucous content included glycogene and/or oxidable dioles [periodic acid/Schiff (PAS)+], neutral or acid-rich (PAS/AB pH 2.5+), sialic acid residues (KOH/PAS+) and acid sulphate [Aldehyde fuchsin (AF)+] glycoproteins. However the mucus content was not the same in stomach, small and large intestine. The mucus content of stomach included only glycogene and/or oxidable dioles and sialic acid residues. Besides these histochemical methods, the localization of HA was detected using biotinylated hyaluronic acid binding protein labeled with streptavidin-fluorescein isothiocyanate (FITC). In the extracellular matrix of the submucosa, the reaction for HA was evident. Since HA was located in submucosa beneath the epithelial layer of gastrointestinal system, it has a significant role in hydric balance, and essential to provide the gastrointestinal system integrity and functionality. According to biometric results, there were statistical differences between small and large intestine in terms of the amount of material stained positive with PAS/AB, PAS, KOH/PAS and AF/AB. Additionally, number of goblet cells in the small and large intestine was significantly different.

Investigation of dorsal/ventral skin and the parotoid region of Lyciasalamandra billae and Lyciasalamandra luschani basoglui (Urodela: Salamandridae)

In the present study, the parotoid region, dorsal and ventral integuments of Lyciasalamandra billae and Lyciasalamandra luschani basoglui were investigated in terms of localization of hyaluronic acid (HA) and histochemical characteristics. HA immunoreactivity was carried out using biotinylated hyaluronic acid binding protein (B-HABP) labelled with streptavidin-fluorescein isothiocyanate (FITC). HA was mainly localized in the stratum spongiosum of L. billae and L. luschani basoglui for water homeostasis and skin functionality. Light microscopic observations revealed that the dorsal and ventral integuments of L. billae and L. luschani basoglui exhibited basic morphological characteristics of other amphibians: the epidermis was composed of a stratified squamous epithelium and the dermis subdivided into stratum spongiosum and stratum compactum. Two different types of dermal glands (mucous and granular glands) were identified in the spongious dermis of the dorsal and ventral integuments whereas in the parotoid region, three different types of glands (mucous, granular and parotoid glands) were examined.

A Histological Study on Venom Apparatus of Montivipera xanthina (Gray, 1849) (Serpentes, Viperidae)

This is the first report describing morphological and histological structure of venom apparatus in Montivipera xanthina. The venom gland apparatus of M. xanthina was composed of four distinct parts, main venom gland, primary duct, accessory gland and secondary duct. The main venom gland was composed of acini. The accessory gland was formed by long and ramified tubules. Nine fangs were detected in one half of the upper jaw each at different stage of development. Only one tooth was functional and the eight remaining fangs form a replacement series. The venom apparatus of viperid snakes are the most effective venom-delivery system among vertebrates and have been the focus of scientific interests for many years. Despite this interest, there are few studies including venom-delivery system of venomous snakes. The results presented here may be common among venomous snakes and model of the viperid design of the venom apparatus.