© 2000 by European Society of Cardiology
Copyright © 2000, European Society of Cardiology
Increased connexin43 gap junction protein in hamster cardiomyocytes during cold acclimatization and hibernation
aDepartment of Anatomy and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
bAutonomic Neuroscience Institute, Royal Free and University College Medical School, Rowland Hill Street, London NW3 2PF, UK
* Corresponding author. Tel.: +44-20-7830-2948; fax: +44-20-7830-2949 g.burnstock{at}ucl.ac.uk
Objective: The physiology of hibernation is characterized by dramatic reductions of heart rate, respiration, metabolism, blood pressure and body temperature and by resistance to ventricular fibrillation. Gap junctions in the heart provide low resistance pathways, facilitating electrical and metabolic coupling between cardiac muscle cells for coordinated action of the heart and tissue homeostasis. The conductance of these junctions, and therefore their function, is likely to be affected by the physiological changes that take place during hibernation. Our objective was to quantitate gap junction protein levels in cold acclimatization, hibernation and arousal. Methods: We have used specific antibodies to connexins 43 and 40, in combination with confocal microscopy, to quantitatively analyze the expression of connexin protein in hamster (Mesocricetus auratus) left ventricles in four animal groups: normal controls at euthermy, cold controls (cold-exposed animals that did not undergo hibernation), hibernating animals and animals aroused from hibernation for 2 h. Results: Connexin40 immunostaining was not detected in ventricular cardiomyocytes in any animal group but connexin43 was found in all groups. Connexin43 expression was significantly enhanced in hibernation and cold control ventricular cardiomyocytes. Total plaque area, numerical density and plaque size were higher in the cold controls and hibernating hamsters compared to normal controls and animals aroused from hibernation. Conclusion: It is possible that the increased size and number of connexin43 gap junction plaques in the cold controls may represent a compensatory response in order to maintain sufficient gap junction communication during physiological conditions that would reduce conductance. These changes may represent a mechanism by which the hamster avoids ventricular fibrillation during hibernation and arousal.
KEYWORDS Hibernation; Gap junction
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  S. Miyazawa, Y. Shimizu, T. Shiina, H. Hirayama, H. Morita, and T. Takewaki Central A1-receptor activation associated with onset of torpor protects the heart against low temperature in the Syrian hamster Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2008; 295(3): R991 - R996. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Mertens, O. Stiedl, S. Steinlechner, and M. Meyer Cardiac dynamics during daily torpor in the Djungarian hamster (Phodopus sungorus) Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2008; 294(2): R639 - R650. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. I. J. Crawford, C. L. Hodgkinson, E. Ivanova, L. B. Logunova, G. J. Evans, S. Steinlechner, and A. S. I. Loudon Influence of torpor on cardiac expression of genes involved in the circadian clock and protein turnover in the Siberian hamster (Phodopus sungorus) Physiol Genomics, November 14, 2007; 31(3): 521 - 530. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. M. Wang, J. Lincoln, J. E. Cook, and D. L. Becker Abnormal Connexin Expression Underlies Delayed Wound Healing in Diabetic Skin Diabetes, November 1, 2007; 56(11): 2809 - 2817. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Yan, A. Burman, C. Nichols, L. Alila, L. C. Showe, M. K. Showe, B. B. Boyer, B. M. Barnes, and T. G. Marr Detection of differential gene expression in brown adipose tissue of hibernating arctic ground squirrels with mouse microarrays Physiol Genomics, April 13, 2006; 25(2): 346 - 353. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. K. VanSlyke and L. S. Musil Cytosolic Stress Reduces Degradation of Connexin43 Internalized from the Cell Surface and Enhances Gap Junction Formation and Function Mol. Biol. Cell, November 1, 2005; 16(11): 5247 - 5257. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. W. Hewett, L. W. Norman, D. Sedmera, R. J. Barker, C. Justus, J. Zhang, S. W. Kubalak, and R. G. Gourdie Knockout of the neural and heart expressed gene HF-1b results in apical deficits of ventricular structure and activation Cardiovasc Res, August 15, 2005; 67(3): 548 - 560. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Saitongdee, D. L. Becker, P. Milner, G. E. Knight, and G. Burnstock Levels of Gap Junction Proteins in Coronary Arterioles and Aorta of Hamsters Exposed to the Cold and During Hibernation and Arousal J. Histochem. Cytochem., May 1, 2004; 52(5): 603 - 616. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. V. CAREY, M. T. ANDREWS, and S. L. MARTIN Mammalian Hibernation: Cellular and Molecular Responses to Depressed Metabolism and Low Temperature Physiol Rev, October 1, 2003; 83(4): 1153 - 1181. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. B. Becker, M. L. Weisfeldt, M. H. Weil, T. Budinger, J. Carrico, K. Kern, G. Nichol, I. Shechter, R. Traystman, C. Webb, et al. The PULSE Initiative: Scientific Priorities and Strategic Planning for Resuscitation Research and Life Saving Therapies Circulation, May 28, 2002; 105(21): 2562 - 2570. [Full Text] [PDF]
|
|
|
|
|
|
T. Opthof and M. B Rook The hibernators heart: Nature's response to arrhythmogenesis? Cardiovasc Res, July 1, 2000; 47(1): 6 - 8. [Full Text] [PDF]
|
|