Morphofunctional evaluation of bullfrog testes: a correlation with fat bodies and seasonality

• Grant number: 14/21383-8
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): December 01, 2014
• Effective date (End): July 31, 2015
• Field of knowledge: Biological Sciences - Morphology - Histology
• Principal researcher: Estela Sasso Cerri
• Grantee: Andressa Baggio
• Home Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Introduction: spermatogenesis and steroidogenesis in bullfrogs (Lithobates catesbeianus) changes according to seasonality. Thus, the tissues undergo morphofunctional changes and also variation in the expression of different factors. It has been suggested that these alterations are transcriptionally controlled by exosome, a complex formed by several subunits, among them RRP6, which is involved in the cell cycle control. Another interesting particularity in anurans is the close relationship between testes and fat bodies. It has been suggested that there is a possible morphofunctional correlation between the interstitial tissue activity and the fat bodies. Objectives: the detection of exosome in anurans has not been described in the literature. Thus, we purposed to localize and quantify the RRP6 immunoexpression in the testes of bullfrogs collected in distinct seasonal periods (winter and summer). Another purpose of this study is to investigate comparatively the morphofunctional features of the interstitial tissue between right and left testes and correlate them to the fat bodies weight. Material e methods: The sections obtained from paraffin-embedded testes of bullfrogs collected in winter and summer will be subjected to the immunohistochemistry or immunofluorescence for detection of RRP6. The RRP6-immunolabeled testicular area will be obtained by using an Image Analysis System (LAS4, Leica). For the bilateral and comparative analysis of the testicular interstitial tissue, the sections will be stained by picrosirius and the birrefringent collagen content will be obtained. Some sections will also be subjected to the immunohistochemical and immunofluorescence reaction for detection of 17²-HSD6 (steroidogenic activity) and VEGF (blood vessels marker). The quantitative results (RRP6 immunoexpression and collagen content) will be evaluated by statistical analyses. (AU)