|
| |
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
Journal of Experimental Biology, Vol 198, Issue 6 1313-1325, Copyright © 1995 by Company of Biologists
JOURNAL ARTICLES |
SM Secor and J Diamond
Department of Physiology, University of California at Los Angeles School of Medicine 90095-1751, USA.
Burmese pythons normally consume large meals after long intervals. We measured gut contents, O2 consumption rates, small intestinal brush-border uptake rates of amino acids and glucose, organ masses and blood chemistry in pythons during the 30 days following ingestion of meals equivalent to 25% of their body mass. Within 1-3 days after ingestion, O2 consumption rates, intestinal nutrient uptake rates and uptake capacities peaked at 17, 6-26 and 11-24 times fasting levels, respectively. Small intestinal mass doubled, and other organs also increased in mass. Changes in blood chemistry included a 78% decline in PO2 and a large 'alkaline tide' associated with gastric acid section (i.e. a rise in blood pH and HCO3- concentrations and a fall in Cl- concentration). All of these values returned to fasting levels by the time of defecation at 8-14 days. The response of O2 consumption (referred to as specific dynamic action, SDA) is the largest, and the upregulation of intestinal nutrient transporters the second largest, response reported for any vertebrate upon feeding. The SDA is a large as the factorial rise in O2 consumption measured in mammalian sprinters and is sustained for much longer. The extra energy expended for digestion is equivalent to 32% of the meal's energy yield, with much of it being measured before the prey energy was absorbed.
This article has been cited by other articles:
|
|
 |
|
  S. M. Secor, J. S. Lane, E. E. Whang, S. W. Ashley, and J. Diamond Luminal nutrient signals for intestinal adaptation in pythons Am J Physiol Gastrointest Liver Physiol, December 1, 2002; 283(6): G1298 - G1309. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Overgaard and T. Wang Increased blood oxygen affinity during digestion in the snake Python molurus J. Exp. Biol., November 1, 2002; 205(21): 3327 - 3334. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Wang, J. Altimiras, and M. Axelsson Intracardiac flow separation in an in situ perfused heart from Burmese python Python molurus J. Exp. Biol., September 1, 2002; 205(17): 2715 - 2723. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. C. Steyermark, M. M. Lam, and J. Diamond Quantitative evolutionary design of nutrient processing: Glucose PNAS, June 25, 2002; 99(13): 8754 - 8759. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. M. Starck and K. Beese Structural flexibility of the small intestine and liver of garter snakes in response to feeding and fasting J. Exp. Biol., May 15, 2002; 205(10): 1377 - 1388. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Wang, E. W. Taylor, D. Andrade, and A. S. Abe Autonomic control of heart rate during forced activity and digestion in the snake Boa constrictor J. Exp. Biol., March 12, 2002; 204(20): 3553 - 3560. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. F. Bennett and J. W. Hicks Postprandial exercise: prioritization or additivity of the metabolic responses? J. Exp. Biol., March 8, 2002; 204(12): 2127 - 2132. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. Secor, D. Fehsenfeld, J. Diamond, and T. E. Adrian Responses of python gastrointestinal regulatory peptides to feeding PNAS, November 9, 2001; (2001) 241524698. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Starck and K Beese Structural flexibility of the intestine of Burmese python in response to feeding J. Exp. Biol., January 1, 2001; 204(2): 325 - 335. [Abstract] [PDF]
|
|
|
|
|
|
S. M. Secor, E. E. Whang, J. S. Lane, S. W. Ashley, and J. Diamond Luminal and systemic signals trigger intestinal adaptation in the juvenile python Am J Physiol Gastrointest Liver Physiol, December 1, 2000; 279(6): G1177 - G1187. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Hicks, T Wang, and A. Bennett Patterns of cardiovascular and ventilatory response to elevated metabolic states in the lizard Varanus exanthematicus J. Exp. Biol., January 8, 2000; 203(16): 2437 - 2445. [Abstract] [PDF]
|
|
|
|
|
|
S. Secor, J. Hicks, and A. Bennett Ventilatory and cardiovascular responses of a python (Python molurus) to exercise and digestion J. Exp. Biol., January 8, 2000; 203(16): 2447 - 2454. [Abstract] [PDF]
|
|
|
|
 |
|
 M. Busk, F. B. Jensen, and T. Wang Effects of feeding on metabolism, gas transport, and acid-base balance in the bullfrog Rana catesbeiana Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2000; 278(1): R185 - R195. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Starck Phenotypic flexibility of the avian gizzard: rapid, reversible and repeated changes of organ size in response to changes in dietary fibre content J. Exp. Biol., January 11, 1999; 202(22): 3171 - 3179. [Abstract] [PDF]
|
|
|
|
|
|
S. M. Secor, D. Fehsenfeld, J. Diamond, and T. E. Adrian Responses of python gastrointestinal regulatory peptides to feeding PNAS, November 20, 2001; 98(24): 13637 - 13642. [Abstract] [Full Text] [PDF]
|
|
