Journal of Comparative Physiology B

, Volume 154, Issue 6, pp 593–599 | Cite as

Relationship between exogenous fuel availability and performance by teleost and elasmobranch hearts

  • William R. Driedzic
  • Tom Hart
Article

Summary

Performance by perfused isolated hearts of sea raven (Hemitripterus americanus) and skate (Raja erinecea), representatives of teleost and elasmobranch fishes, respectively, was monitored over a 30 min period under conditions of variable metabolic fuel availability. In both preparations initial cardiac output and hence fuel delivery to the myocardia were comparable to in vivo levels. Pressure development and hence overall work rate of the sea raven heart was also similar to in vivo levels.

Fuel deprived sea raven hearts entered into a modest but significant contractile failure which could be prevented by the inclusion of 10 mM glucose or 1.0 mM palmitate in the perfusion medium. Addition of the glycolytic inhibitor iodoacetate to the medium resulted in rapid heart failure. Performance in the presence of iodoacetate could be improved by the inclusion of palmitate, lactate, or acetoacetate in the perfusion media but only high physiological levels of palmitate could completely alleviate the effect of iodoacetate.

The inclusion of 1.0 mM palmitate in the perfusion medium of skate hearts resulted in a significant decrease in performance relative to fuel deprived hearts. Addition of iodoacetate to the medium resulted in rapid contractile failure. Hearts perfused with medium containing both iodoacetate and acetoacetate performed as well as fuel deprived hearts, indicating that this ketone body is an effective metabolic fuel.

The performance data reported here are consistent with a previously established biochemical framework. The teleost heart has the capability of utilizing exogenous fatty acid as a metabolic fuel and this substrate may be able to support the contractile process independently. In contrast, fatty acid metabolism in the elasmobranch heart is poorly developed and appears to be more dependent upon the catabolism of blood borne ketone bodies.

Keywords

Palmitate Ketone Body Acetoacetate Perfusion Medium Iodoacetate 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Beamish FWH (1968) Glycogen and lactic acid concentrations in Atlantic cod (Gadus morhua) in relation to exercise. J Fish Res Board Can 25:837–851Google Scholar
  2. Chavin W, Young JE (1970) Factors in the determination of normal serum glucose levels of goldfish,Carassius auratus L. Comp Biochem Physiol 33:629–653Google Scholar
  3. Driedzic WR (1978) Carbohydrate metabolism in the perfused dogfish heart. Physiol Zool 51:42–49Google Scholar
  4. Driedzic WR (1983) Myoglobin function in fish heart. Comp Biochem Physiol 76A:487–494Google Scholar
  5. Driedzic WR, Kiceniuk JW (1976) Blood lactate levels in freeswimming rainbow trout (Salmo gairdneri) before and after strenuous exercise resulting in fatigue. J Fish Res Board Can 33:173–176Google Scholar
  6. Driedzic WR, Phleger CF, Fields JHA, French C (1978) Alterations in energy metabolism associated with the transition from water to air breathing in fish. Can J Zool 56:730–735Google Scholar
  7. Driedzic WR, Scott DL, Farrell AP (1983) Aerobic and anaerobic contribution to energy metabolism in perfused isolated sea raven (Hemitripterus americanus) hearts. Can J Zool 61:1880–1883Google Scholar
  8. Driedzic WR, Stewart JM (1982) Myoglobin content and the activities of enzymes of energy metabolism in red and white fish hearts. J Comp Physiol 149:67–73Google Scholar
  9. Driedzic WR, Stewart JM, Scott DL (1982) The protective effect of myoglobin during hypoxic perfusion of isolated fish hearts. J Mol Cell Cardiol 14:673–677Google Scholar
  10. Fellows FCI, Hird FJR (1981) Fatty acid binding proteins in the serum of various animals. Comp Biochem Physiol 68B:83–87Google Scholar
  11. Fellows CI, Hird FJR, McLean RM, Walker TI (1980) A survey of the non-esterified fatty acids and binding proteins in the plasma of selected animals. Comp Biochem Physiol 67B:593–597Google Scholar
  12. Gesser H, Poupa O (1975) Lactate as substrate for force development in hearts with different isoenzyme patterns of lactate dehydrogenase. Comp Biochem Physiol 52B:311–313Google Scholar
  13. Hansen CA, Sidell BD (1983) Atlantic hagfish cardiac muscle: mechanical and metabolic response to anoxia. Am J Physiol 244R:356–362Google Scholar
  14. Jackson DC, Heisler N (1982) Plasma ion balance of submerged anoxic turtles at 3 °C: the role of calcium lactate formation. Respir Physiol 49:159–174Google Scholar
  15. Katz AM, Messineo FC (1981) Lipid-membrane interactions and the pathogenesis of ischemic damage in the myocardium. Circ Res 48:1–16Google Scholar
  16. Larsson A, Fänge R (1977) Cholesterol and free fatty acids (FFA) in the blood of marine fish. Comp Biochem Physiol 57B:191–196Google Scholar
  17. Neely JR, Rovetto MJ, Oram JF (1972) Myocardial utilization of carbohydrate and lipids. Prog Cardiovasc Dis 15:289–329Google Scholar
  18. Patton S, Zulak IM, Trams EG (1975) Fatty acid metabolism via triglyceride in the salmon heart. J Mol Cell Cardiol 7:857–865Google Scholar
  19. Rovetto MJ, Lamberton WF, Neely JR (1975) Mechanisms of glycolytic inhibition in ischemic rat hearts. Circ Res 37:742–751Google Scholar
  20. Satchell GH (1971) Circulation in fishes. Cambridge University Press, LondonGoogle Scholar
  21. Stevens ED, Black EC (1966) The effect of intermittent exercise on carbohydrate metabolism in rainbow trout,Salmo gairdneri. J Fish Res Board Can 23:471–485Google Scholar
  22. Wardle CS (1978) Non-release of lactic acid from anaerobic swimming muscle of plaice (Pleuronectes platessa L.): a stress reaction. J Exp Biol 77:141–155Google Scholar
  23. Yatani A, Fujino T, Kinoshita K, Goto M (1981) Excess lactate modulates ionic currents and tension components in frog atrial muscle. J Mol Cell Cardiol 13:147–161Google Scholar
  24. Zammit VA, Newsholme EA (1979) Activities of enzymes of fat and ketone-body metabolism and effects of starvation on blood concentrations of glucose and fat fuels in teleost and elasmobranch fish. Biochem J 184:313–322Google Scholar

Copyright information

© Springer-Verlag 1984

Authors and Affiliations

  • William R. Driedzic
    • 1
  • Tom Hart
    • 2
  1. 1.Mount Desert Island Biological LaboratorySalsbury CoveUSA
  2. 2.Biology DepartmentMount Allison UniversitySackvilleCanada

Personalised recommendations