Study On Expression Of AQP1/AQP5 In The Bactrian Camel’s Salivary Glands

The metabolic balance of water in salivary glands has an important significance in the Bactrian camel to maintain their normal physiological function. To adapt to the harsh conditions— cold, hot, arid, and poor grazing—of deserts or semi-deserts, the Bactrian camel’s salivary glands have acquired many special abilities and attributes.The Bactrian camel’s salivary glands have important role in promoting oral slippery,moist food and saliva secretion, because of these unique features and structures.Objective: In this study, we compare salivary gland cells and AQP1/5 expression between cattle and Bactrian camel, to investigate the feeding mechanism of the Bactrian camel adapt to extremely arid environment. We detect the Bactrian camel and cattle salivary glands function and configuration features to provide cells and molecular basis for us to understand the good adaptation mechanism of the Bactrian camel to the extremely arid environment.Methods: HE staining, Silver staining and Immunohistochemical methods were used to investigate their structure and to analyze expression and localization of AQP1/5 in salivary glands. Conventional statistical method was used to analyze statistic data of salivary glands.Results: In the parotid gland, the number of acinars were signi?cantly higher in the Bactrian camel compared to the cattle, while the number of acinars were signi?cantly lower in the sublingual and submandibular glands. Silver staining demonstrated the presence of neuroendocrine cells. Neuroendocrine cells were shown to be distributed in their secretory duct nearby. The result of immunohistochemistry shows that AQP1/5 are found in secretory duct and basement membrane of acinar cells in salivary glands. In addition, in the salivary glands, the expression of AQP1 was no significant difference in the Bactrian camel compared to the cattle, but in the sublingual and submandibular glands, relative values of AQP5 were signi?cantly higher in the Bactrian camel compared to the cattle. In the parotid gland, relative values of AQP5 were signi?cantly lower in the Bactrian camel compared to the cattle.Conclusion: The salivary glands features of the Bactrian camel proved the adaptability to arid desert environment, high expression of AQPs in the salivary glands cells contribute to transepithelial water movement. AQPs were shown to be involved in a variety of processes such as food lubrication, oral moist and food digestion, which supplied some molecular basis for the Bactrian camel to be still able to eat when they were hungry and thirsty.