General Histology and Cytology
Microanatomy of the renicule of Balaena mysticetus
Article first published online: 26 JAN 2005
Copyright © 1986 Wiley-Liss, Inc.
The Anatomical Record
Volume 214, Issue 2, pages 118–129, February 1986
How to Cite
Henk, W. G., Abdelbaki, Y. Z., Haldiman, J. T. and Albert, T. F. (1986), Microanatomy of the renicule of Balaena mysticetus. Anat. Rec., 214: 118–129. doi: 10.1002/ar.1092140204
- Issue published online: 26 JAN 2005
- Article first published online: 26 JAN 2005
- Manuscript Accepted: 17 SEP 1985
- Manuscript Received: 4 FEB 1985
Renicules from twelve bowhead whales (Balaena mysticetus) were examined utilizing light, scanning electron, and transmission electron microscopes. The basic organization of the renicule into capsule, cortex, sporta perimedullaris, medulla, and calyx is described. Despite less than perfect preservation resulting from environmental and logistical conditions at the collecting sites, it has been possible to document the basic microstructure of most components of the renicule of this endangered species. Several unusual features were observed. The absence of smooth muscle fibers (other than in vessel walls) from the capsule, sporta perimedullaris, and calyx wall is a departure from what is reported in other cetaceans as is the consistent presence of arcuate arteries in the substance of the sporta perimedullaris. Large subcapsular veins are present but do not appear to represent connecting elements in an alternative venous return through capsular and interrenicular veins. Elastic fibers are seen only in the sporta perimedullaris and the calyx wall, whereas reticular fibers are most abundant in the medullary stroma. Finally, enlarged cells with clear cytoplasm are seen in the tunica media of the glomerular afferent arterioles extending a variable, but always considerable, distance toward the interlobular arteriole. These cells are presumed to represent an extended array of the epithelioid cells common in the afferent arterioles of the juxtaglomerular apparatus of other mammalian kidneys.