Renal Microvasculature in Lyle's Flying Fox (Pteropus lylei)

Abstract

Objective: The purpose of this study was to elucidate the renal microvasculature of Lyleûs flying fox.

Methods: The kidneys of twelve adult Lyleûs flying foxes of both sexes were processed by using vascular corrosion cast technique combined with SEM.

Results: It was found that arcuate arteries at the corticomedullary junctions give off several interlobular arteries, which run perpendicularly into the renal cortex. The interlobular artery branches into two sets of vessels. Firstly, aglomerular arteriole divides into capsular and peritubular capillary plexus without forming glomeruli. Secondly, an afferent arteriole, a branch of the interlobular artery, breaks into the glomerular capillary plexus that gathers to form a single efferent arteriole. An efferent arteriole gives rise to a peritubular capillary plexus and vasa recta. A peritubular capillary forms a plexus among renal tubules. Vasa recta are straight vessels that run parallel to Henleûs loops and collecting ducts in the outer medulla. In addition, vasa recta form U-shaped loops in the inner medulla. Moreover, the fenestrated type of capillaries is observed. It was found that high numbers of the fenestration were seen in the glomerular capillary plexus and venous limbs of vasa recta in the outer medulla. In contrast, fewer knobs were presented in the loops of vasa recta in the inner medulla and peritubular capillary plexus. Both peritubular capillary plexus and vasa recta collect the blood into interlobular and arcuate veins.

Conclusion: In this investigation, the aglomerular arteriole might be an important shunting of the blood, while this animal alters the position immediately. With the advantages of this technique, fenestrated capillaries are demonstrated which are related to the functions of each tubule. Moreover, the microvascular patterns of the kidney in this animal are similar to that in human. Therefore, it is a suitable model for renal microvascular investigation.