Immunohistochemical detection of glucose transporters class I subfamily in the mouse, rat and human testis

Kersti Kokk^{1, 2}, Esko Veräjänkorva², Xiao-Ke Wu^{2, 4}, Helle Tapfer¹, Elle Põldoja¹, Pasi Pöllänen^{2, 3}

¹Department of Anatomy, University of Tartu, Estonia, ²Department of Anatomy, ³Department of Obstetrics and Gynecology, University of Turku, Finland ⁴Department of Obstetrics and Gynecology, Jinling Hospital, Nanjing University, China

Key words: glucose transporters, testis, immunohistochemistry.

Summary. A family of glucose transporters (GLUT) mediates the cellular uptake of glucose at the plasma membrane by facilitated diffusion. We investigated the presence of isoforms GLUT1-4 of class I subfamilies in different types of cells in the mouse, rat and human testis by indirect immunofluorescence technique. Immunocytochemical analyses demonstrated that GLUT1 was expressed in the rat testis, GLUT2 in the mouse and rat testis, GLUT3 in the mouse, rat and human testis and GLUT4 was not presented in the testis at all. A very intensive positive immunoreaction for GLUT3 was found in Sertoli cells, peritubular myoid cells, macrophage-like interstitial cells, testicular endothelial cells and early spermatocytes. GLUT3 positive cells were not found in the luminal part of Sertoli cells, spermatids or Leydig cells. The present results suggest that glucose uptake in different testicular cells is mediated by GLUT1, GLUT2 and GLUT3 and the GLUT3 was the prominent glucose transporter type in the testicular cells.

Correspondence to K. Kokk, Department of Anatomy, University of Tartu, Biomedicum, Ravila 19, 50411 Tartu, Estonia. E-mail: kerstiko@ut.ee

Received 10 June 2003, accepted 25 November 2003