spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Full Text (PDF)
Right arrow References
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Conley, K. E.
Right arrow Articles by Weibel, E. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Conley, K. E.
Right arrow Articles by Weibel, E. R.

Journal of Experimental Biology, Vol 198, Issue 3 739-746, Copyright © 1995 by Company of Biologists

JOURNAL ARTICLES

Heart mitochondrial properties and aerobic capacity are similarly related in a mammal and a reptile

KE Conley, KA Christian, H Hoppeler and ER Weibel
Department of Radiology, University of Washington, Seattle 98195.

The heart mitochondrial properties and the aerobic capacity (VO2max) of the rat (Sprague-Dawley breed) and the Cuban iguana (Cyclura nubila) were used to evaluate the relationship between the oxidative capacity of the heart and the maximum oxygen delivery rate. Both species are active at body temperatures of 37-39 degrees C, have similar heart mitochondrial volumes [Vmt; 0.43 +/- 0.02 ml (S.E.M.) in the rat and 0.48 +/- 0.02 ml in the iguana] and differ less than twofold in VO2max (29.2 +/- 1.6 and 16.9 +/- 0.6 ml min-1, respectively). We found that Vmt was closely correlated with VO2max in the rat (r2 = 0.77, P < 0.005) and the iguana (r2 = 0.82; P < 0.001). Furthermore, the inner mitochondrial membrane (cristae) area (Sim) per unit VO2max did not differ between the rat and the iguana (0.60 +/- 0.02 and 0.71 +/- 0.02 m2 min ml-1 O2, respectively). This correspondence of Sim/VO2max indicates that the rat and the iguana have the same cardiac oxidative capacity at the maximum oxygen delivery rate. These results suggest that, despite the differences between the cardiovascular systems of these species, the cardiac cost of delivering oxygen at the aerobic capacity is similar in this mammal and this reptile.




© The Company of Biologists Ltd 1995