Objective: Salivary glands pass through various stages of prenatal and postnatal development. This process is a highly regulated event governed by signaling molecules, growth factors and hormones. Submandibular salivary gland is an excellent model to study salivary gland morphogenesis. It has been reported that alternations in endocrine hormones can affect morphological and functional states of salivary gland formation and for this purpose the current study was designed to investigate the effects of exogenous administration of T3 on the histology of the submandibular salivary gland during early postnatal development.
Materials and Methods: Following ethical approval, twenty four healthy Wister rats were obtained. Twelve were taken at the age of three weeks and divided into control (A1) and experimental (B1) groups. Remaining twelve were taken at the age of seven weeks and divided into control (A2) and experimental (B2) groups. The experimental animals were administered 0.5 mg/kg body weight of T3 while controls were given normal saline. The animals of group A1 and B1 were sacrificed at week 5 and those of group A2 and B2 at week nine. The submandibular glands were dissected out and their morphological structure was observed. The combined weight and volume of submandibular and sublingual gland was taken. Hematoxylin and Eosin staining was performed to assess any histological changes in the parenchyma and stromal components of the submandibular salivary gland.
Results: No significant gross and histological changes in parenchyma and stroma of submandibular salivary gland tissue were observed in control and experimental groups at week five and week nine. No statistically significant difference was found in the combined weight and volume of submandibular and sublingual glands through the independent sample t-test.
Conclusion: Exogenous administration of T3 at a lower dose did not cause significant changes in the postnatal development of the submandibular salivary gland.
Key words: Submandibular salivary gland, development, thyroid hormone, postnatal
|
