Journal of Camel Practice and Research

Aquaporin (AQP) 1 and AQP2 belongs to the aquaporin water channel family, which play a main role in reabsorption of water from the renal tubular fluid to concentrate urine. With paraffin section method combined with transmission electron microscopy, the microstructure and ultrastructure of bactrian camel (Camelus bactrianus) kidney was observed. We studied nephron segment-specific expression of AQP1 and AQP2 using immunohistochemical staining on paraffin sections of camel kidneys. We found that the microstructure and ultrastructure of kidneys in camel, was similar to those of other animals. However, the structure of the various parts of nephron were developed, especially, proximal tubule brush border. Moreover, strong expression of AQP1 was observed in the apical and basolateral membrane of epithelial cells in proximal tubule and Henle's loop descending limb. AQP2 was strongly expressed in apical membrane and cytoplasm of principal cells in the collecting duct and epithelial cells in the distal convoluted tubule. In conclusion, strong expression of AQP1 and AQP2 in the camel kidney showed some differences from other species in renal trans-epithelial water transport, these results enhanced our better understanding of special water metabolism mechanisms, to some extent, it may be one of the secrets of camel to survive in the extremely arid and harsh environment.