General Histology and Cytology
Activation of osteoclasts and the repopulation of bone surfaces following hibernation in the bat, Myotis lucifugus
Article first published online: 26 JAN 2005
Copyright © 1985 Wiley-Liss, Inc.
The Anatomical Record
Volume 213, Issue 4, pages 481–495, December 1985
How to Cite
Doty, S. B. and Nunez, E. A. (1985), Activation of osteoclasts and the repopulation of bone surfaces following hibernation in the bat, Myotis lucifugus. Anat. Rec., 213: 481–495. doi: 10.1002/ar.1092130403
- Issue published online: 26 JAN 2005
- Article first published online: 26 JAN 2005
- Manuscript Accepted: 12 JUN 1985
- Manuscript Received: 26 OCT 1983
In previous studies of the adult bat, Myotis lucifugus, bone loss that occurred during the hibernating period was attributed to osteocytic osteolysis, rather than osteoclastic activity. We have used histochemistry and light and electron microscopy to determine the functional state of the skeleton during the hibernating period. We find that during hibernation the marrow cavity of the long bones is filled with lipid deposits interspersed with vascular sinusoids containing mononuclear cells and red blood cells. The lipid deposits are found within fat cells and at extracellular sites. Hematopoietic cells are absent, osteoclasts are absent, and the bone surfaces are covered with quiescent bone-lining cells. Osteocytes retain their structural integrity and maintain canalicular systems with the bone lining cells and with other osteocytes.
During the arousal period, osteoclasts reappear on the bone surface, followed in time by increased numbers of osteoblast-like cells. Perivascular cells undergo structural hypertrophy. Many mononuclear cells are now found in extravascular sites. The lipid content in the marrow is gradually reduced and replaced by hematopoietic cells. Each of these events occurs in a repeatable sequence that is related to the state of hibernation of Myotis lucifugus.