Somatosensory organization and behavior in naked mole-rats: II. Peripheral structures, innervation, and selective lack of neuropeptides associated with thermoregulation and pain
Version of Record online: 12 AUG 2003
Copyright © 2003 Wiley-Liss, Inc.
Journal of Comparative Neurology
Volume 465, Issue 1, pages 104–120, 6 October 2003
How to Cite
Park, T. J., Comer, C., Carol, A., Lu, Y., Hong, H.-S. and Rice, F. L. (2003), Somatosensory organization and behavior in naked mole-rats: II. Peripheral structures, innervation, and selective lack of neuropeptides associated with thermoregulation and pain. J. Comp. Neurol., 465: 104–120. doi: 10.1002/cne.10824
- Issue online: 12 AUG 2003
- Version of Record online: 12 AUG 2003
- Manuscript Accepted: 3 MAY 2003
- Manuscript Revised: 24 APR 2003
- Manuscript Received: 13 DEC 2002
- Campus Research Board, University of Illinois at Chicago
- National Institutes of Health. Grant Numbers: R01 NS34692, R29 DC02850
- substance P;
African naked mole-rats are subterranean rodents that have a robust orienting response to stimulation of unique vibrissa-like body hairs that are widely spaced over an otherwise hairless skin. To determine whether these large body hairs have a specialized organization similar to facial vibrissae, the structure and innervation of facial vibrissa follicles, body hair follicles, and intervening skin in naked mole-rats was compared with that in rats and a furred African mole-rat species (the common mole-rat). Immunofluorescence and lectin-binding analyses revealed that the body hair follicles in naked mole-rats were exceptionally large and well innervated, similar to guard hairs of furred species. However, these body vibrissae lacked the anatomic specializations and unique types of innervation affiliated with follicle sinus complexes of facial vibrissae. In contrast to the furred species, naked mole-rats had a paucity of Aβ-fiber Merkel endings at all peripheral locations. Naked mole-rats also were completely lacking in cutaneous C-fibers immunoreactive for substance P and calcitonin gene-related peptide. In contrast, the hairless skin of the naked mole-rats had an exceptional abundance of presumptive Aδ-fibers. The unusual features of the cutaneous innervation in naked mole-rats are presumably adaptations to their subterranean environment and that they are the only known poikilothermic mammal. The features of this mammalian model system provide unique opportunities to discriminate mechanisms related to tactile spatial orientation, vascular regulation, and nociception. J. Comp. Neurol. 465:104–120, 2003. © 2003 Wiley-Liss, Inc.