Subcellular localization of GLUT1 in the acini and striated ducts of the sublingual major salivary glands in female rats (immunohistochemical study)

Background: Sublingual salivary gland (SLGs) is one of the major salivary glands that is predominantly mucous in nature. The glucose transporter 1 (GLUT1) is responsible for the transport of monosaccharides and is localized in the parotid and submandibular major salivary glands, however GLUT1 localization in the SLGs is hitherto unknown. Objective: To investigate the distribution patterns of GLUT1 in adult female SLG´s lobular structures of the control female rats. Material and method: The SLGs were assessed by hematoxylin and eosin (H&E) and Masson trichrome. The GLUT1 immunohistochemistry was utilized to localize the protein in the SLG tissue, followed by histomorphometric analysis of the GLUT1 immunoreaction´s optical intensity. Results: The SLG tissue revealed GLUT1 localization in the mucous acini and in the striated ducts (SDs). Histomorphometric analysis revealed a lesser intensity of GLUT1 immunoreaction in the acini in comparison to the SDs (P= 0.000) Conclusion: GLUT1+ immunolabelling was depicted in the acini and the SDs of the SLGs, however the optical intensity of the GLUT1 immunolabelling was significantly higher in the SDs than the acini, which may reflect a higher energy requirement in the SDs. Based on the localization of GLUT1 in the SLG, new treatment options targeting metabolic pathways including GLUT1 inhibitors may offer a promising therapeutic modality in glandular diseases and cancers. Keywords: Sublingual salivary gland, GLUT1, striated ducts, female rats