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. 1968 Sep;198(2):251–276. doi: 10.1113/jphysiol.1968.sp008605

Shivering and non-shivering thermogenesis during summit metabolism in young lambs

G Alexander, D Williams
PMCID: PMC1365322  PMID: 5698273

Abstract

1. Summit metabolism of lambs declined steadily from about 3·5 l. O2/kg.hr during the first day of life, to about 2·0 l. O2/kg.hr at 2 months of age.

2. The contributions of shivering and non-shivering thermogenesis to these changes were estimated by three independent methods; non-shivering thermogenesis was stimulated by catecholamines in a thermoneutral environment, shivering was suppressed by curariform drugs during summit metabolism, and an attempt was made to suppress non-shivering thermogenesis during summit metabolism by use of the sympatholytic drugs phentolamine and propranolol. Drugs were given by intravenous infusion during measurement of oxygen consumption in a closed circuit respiration chamber.

3. `Resting' metabolic rate of lambs during the first day of life was increased two to three-fold, from 1 l. O2/kg.hr, by either adrenaline or noradrenaline infused at 1-10 μg/kg.min. The increase declined with increasing age of lamb and was virtually absent by 3 weeks. The response to catecholamines appeared maximal at the dose levels used.

4. Muscular paralysis induced by suxamethonium or gallamine reduced summit metabolism by about 2 l. O2/kg.hr in all lambs examined within the first 2 months of life. The residual metabolic rate, and the metabolic response to catecholamines under thermoneutral conditions, declined with age in the same manner, and their magnitudes were similar.

5. Summit metabolism in lambs aged up to 2 months was depressed to varying degrees by the sympathetic inhibitors phentolamine, propranolol and hexamethonium. The depression with propranolol was greater, and the decline with age clearer, than with phentolamine. Hexamethonium and phentolamine depressed blood pressure, propranolol decreased heart rate and phentolamine and propranolol each suppressed shivering in some experiments.

6. In 1 day-old lambs estimates of non-shivering thermogenesis, by the various methods, ranged from 0·8 to 1·4 l. O2/kg.hr (mean 1·1 l. or 31% of summit metabolism), and the estimates of shivering ranged from 1·3 to 1·9 l. O2/kg.hr (mean 1·6 l. or 46% of summit metabolism). However, in lambs 1-month old, estimates of non-shivering thermogenesis from sympathetic inhibition (0·6 and 0·8 l. O2/kg.hr) were considerably higher than estimates from muscular paralysis or stimulation by catecholamines (0·2 and 0·1 l. O2/kg.hr). It is suggested that the depression of summit metabolism by the sympathetic inhibitors is not solely due to specific inhibition of non-shivering thermogenesis, at least in the older lambs.

7. The possession of a non-shivering thermogenic mechanism in addition to shivering is of clear survival value to new-born lambs.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Alexander G., Mills S. C., Scott T. W. Changes in plasma glucose, lactate and free fatty acids in lambs during summit metabolism and treatment with catecholamines. J Physiol. 1968 Sep;198(2):277–289. doi: 10.1113/jphysiol.1968.sp008606. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. BOSHART C. R., SMITH T. C., WILL L., PIRRE A., PERRINE J., RINGLER I. ACTION OF PHENTOLAMINE ON RAT ADIPOSE TISSUE. J Pharmacol Exp Ther. 1964 Feb;143:221–229. [PubMed] [Google Scholar]
  3. Brück K., Wünnenberg W. Beziehung zwischen Thermogenese im "braunen" Fettgewebe, Temperatur im cervicalen Anteil des Vertebralkanals und Kältezittern. Pflugers Arch Gesamte Physiol Menschen Tiere. 1966;290(2):167–183. [PubMed] [Google Scholar]
  4. DAWES G. S., MESTYAN G. CHANGES IN THE OXYGEN CONSUMPTION OF NEW-BORN GUINEA-PIGS AND RABBITS ON EXPOSURE TO COLD. J Physiol. 1963 Aug;168:22–42. doi: 10.1113/jphysiol.1963.sp007176. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. DAWKINS M. J., HULL D. BROWN ADIPOSE TISSUE AND THE RESPONSE OF NEW-BORN RABBITS TO COLD. J Physiol. 1964 Aug;172:216–238. doi: 10.1113/jphysiol.1964.sp007414. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. FRITZ I. B., DAVIS D. G., HOLTROP R. H., DUNDEE H. Fatty acid oxidation by skeletal muscle during rest and activity. Am J Physiol. 1958 Aug;194(2):379–386. doi: 10.1152/ajplegacy.1958.194.2.379. [DOI] [PubMed] [Google Scholar]
  7. HERD J. A., BARGER A. C. SIMPLIFIED TECHNIQUE FOR CHRONIC CATHETERIZATION OF BLOOD VESSELS. J Appl Physiol. 1964 Jul;19:791–792. doi: 10.1152/jappl.1964.19.4.791. [DOI] [PubMed] [Google Scholar]
  8. HILL J. R. The oxygen consumption of new-born and adult mammals. Its dependence on the oxygen tension in the inspired air and on the environmental temperature. J Physiol. 1959 Dec;149:346–373. doi: 10.1113/jphysiol.1959.sp006344. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. HULL D. OXYGEN CONSUMPTION AND BODY TEMPERATURE OF NEW-BORN RABBITS AND KITTENS EXPOSED TO COLD. J Physiol. 1965 Mar;177:192–202. doi: 10.1113/jphysiol.1965.sp007585. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. HULL D. PRONETHALOL AND THE OXYGEN CONSUMPTION OF NEW-BORN RABBITS. J Physiol. 1964 Sep;173:13–23. doi: 10.1113/jphysiol.1964.sp007439. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Heim T., Hull D. The effect of propranalol on the calorigenic response in brown adipose tissue of new-born rabbits to catecholamines, glucagon, corticotrophin and cold exposure. J Physiol. 1966 Nov;187(2):271–283. doi: 10.1113/jphysiol.1966.sp008088. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Hull D., Segall M. M. Heat production in the new-born rabbit and the fat content of the brown adipose tissue. J Physiol. 1965 Dec;181(3):468–477. doi: 10.1113/jphysiol.1965.sp007775. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Hull D., Segall M. M. Sympathetic nervous control of brown adipose tissue and heat production in the new-born rabbit. J Physiol. 1965 Dec;181(3):458–467. doi: 10.1113/jphysiol.1965.sp007774. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Hull D. The structure and function of brown adipose tissue. Br Med Bull. 1966 Jan;22(1):92–96. doi: 10.1093/oxfordjournals.bmb.a070447. [DOI] [PubMed] [Google Scholar]
  15. JENSEN C., EDERSTROM H. E. Development of temperature regulation in the dog. Am J Physiol. 1955 Nov;183(2):340–344. doi: 10.1152/ajplegacy.1955.183.2.340. [DOI] [PubMed] [Google Scholar]
  16. Jenkinson D. M., Noble R. C., Thompson G. E. Adipose tissue and heat production in the new-born ox (Bos taurus). J Physiol. 1968 Apr;195(3):639–646. doi: 10.1113/jphysiol.1968.sp008479. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. LeBlanc J., Mount L. E. Effects of noradrenaline and adrenaline on oxygen consumption rate and arterial blood pressure in the newborn pig. Nature. 1968 Jan 6;217(5123):77–78. doi: 10.1038/217077a0. [DOI] [PubMed] [Google Scholar]
  18. Moore R. E., Simmonds M. A. Decline with age in the thermogenic response of the young rat to lota-noradrenaline. Fed Proc. 1966 Jul-Aug;25(4):1329–1331. [PubMed] [Google Scholar]
  19. SCOPES J. W., TIZARD J. P. The effect of intravenous noradrenaline on the oxygen consumption of new-born mammals. J Physiol. 1963 Feb;165:305–326. doi: 10.1113/jphysiol.1963.sp007058. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. TAYLOR P. M. Oxygen consumption in new-born rats. J Physiol. 1960 Nov;154:153–168. doi: 10.1113/jphysiol.1960.sp006570. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Wenke M. Effects of catecholamines on lipid metabolism. Adv Lipid Res. 1966;4:69–105. doi: 10.1016/b978-1-4831-9940-5.50010-7. [DOI] [PubMed] [Google Scholar]
  22. Wensvoort P. The development of adipose tissue in sheep foetuses. Pathol Vet. 1967;4(1):69–78. doi: 10.1177/030098586700400107. [DOI] [PubMed] [Google Scholar]

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