The effects of thermogenic agents on hindlimb oxygen consumption in the dog: ICI D7114 and noradrenaline
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The thermogenic action of beta-adrenoceptor agonists may be due, in part, to increased metabolism in skeletal muscle. Previous results suggest that vasoconstriction is also necessary, and that the effect can be blocked by vasodilators. Both noradrenaline and the beta-3 agonist, ICI D7114, were studied using two dog hindlimb protocols. During constant perfusion conditions, ICI D7114 caused a significant increase in hindlimb oxygen consumption although it is a vasodilator. Noradrenaline resulted in a smaller rise in oxygen consumption, and produced a marked vasoconstriction. Both noradrenaline and ICI D7114 resulted in decreased oxygen consumption when the blood flow was allowed to vary in response to the drug treatment. The results suggest that changes in tissue oxygen consumption caused by beta-agonists are not related to vasomotion.
Key wordsBeta-adrenoceptor agonist skeletal muscle thermogenic agents oxygen consumption noradrenaline
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- 1.Foster, D. O., and Frydman, M. L., Can. J. Physiol. Pharmac.57 (1979) 257.Google Scholar
- 3.Colquhoun, E. Q., Hettiarachchi, M., and Clark, M. G., Gen. Pharmac.21 (1990) 141.Google Scholar
- 4.Jansky, L., in: Nonshivering Thermogenesis, p. 159. Ed. L. Jansky. Academia, Prague 1971.Google Scholar
- 6.Ye, J.-M., Colquhoun, E. Q., Hettiarachchi, M., and Clark, M. G., Can. J. Physiol. Pharmac.68 (1990) 119.Google Scholar
- 7.Hannon, J. P., Evonuk, E., and Larson, A. M., Fedn Proc.22 (1963) 783.Google Scholar
- 9.Holloway, B. R., Briscoe, M., Growcott, J. W., Wilson, C., and Stock, M. J., in: Adrenoceptors: Structure, Mechanisms, Functions, p. 313. Birkhäuser Verlag, Basel 1991.Google Scholar
- 13.Bowman, W. C., and Rand, M. S., Textbook of Pharmacology, 2nd edn, p. 5. Blackwell Scientific Publications. Oxford 1980.Google Scholar
- 17.Hogan, M. C., Bebout, D. E., and Wagner, P. D., J. appl. Physiol.70 (1990) 1105.Google Scholar