geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Metabolic and endocrine responses to prolonged exercise in rats under beta 2-adrenergic blockade


, : Metabolic and endocrine responses to prolonged exercise in rats under beta 2-adrenergic blockade. Canadian Journal of Physiology and Pharmacology 67(3): 192-196

The respective roles of allosteric regulators and catecholamines in the control of muscle glycogen breakdown during exercise remain a matter of controversy. This study was designed to reassess the role of the sympathoadrenal system during prolonged exercise in rats. Animals were studied at rest or after treadmill exercise (28 m.min-1; 8% slope) to exhaustion in a control situation or following administration of a specific beta 2-adrenergic receptor antagonist (ICI 118,551, 1 mg.kg-1, i.v.). Running times to exhaustion were 54 and 36 min in control and treated rats, respectively. For the purpose of comparison, another group of control rats was studied after a 36-min exercise bout. The reduction in endurance in treated rats was associated with an impairment in glycogen utilization, as measured by muscle glycogen stores, in soleus muscle but not in superficial vastus lateralis or gastrocnemius lateralis muscles. Utilization of liver glycogen stores was similar in the two groups of animals, but plasma glucose (7 vs. 13 mM) and lactate (4 vs. 7 mM) levels were significantly lower in rats under beta-blockade than in control rats run for 36 min. Plasma free fatty acid and glycerol concentrations were not significantly different between groups. On the other hand, plasma epinephrine concentration was significantly higher in treated rats (13 vs. 5 mM), which might reflect a compensatory increase in adrenal activity. These results suggest that glycogen breakdown during prolonged exercise is under the control of the sympathoadrenal system in predominantly slow-twitch but not in predominantly fast-twitch muscles.

US$29.90

PMID: 2568161


Other references

Kan, S.; Fox, A.J.; Viñuela, F.; Barnett, H.J.; Peerless, S.J., 1983: Delayed CT metrizamide enhancement of syringomyelia secondary to tumor. Six cases of syringomyelia associated with intramedullary tumor were examined by metrizamide myelography and delayed computed tomography. All cases showed opacification of syringomyelic cavities 7-24 hr after myelography. This finding suggests tha...

Koike, M.; Koike, K.; Hiraoka, T., 1981: Structure, function and an inherited defect of 2-oxo acid dehydrogenase multienzyme complexes. Biochemical Society Transactions 9(1): 6-7

Anonymous, 1964: Rationalized timber measurement. Summarizes recommendations of a working party, for measuring timber transported by road (measuring the stacked timber, or weight measurements) or by water (counting the pieces and determining mean volume by random sampling), and indicates comparat...

Balazuc, J., 1979: Research on Laboulbeniomycetes. IV. Description of five species of Laboulbeniales. Revue de mycologie3(4): 393-404

Marquez, H.P.; Puippe, G.; Mathew, R.Philip.; Alkadhi, H.; Pfammatter, T.; Fischer, M.A., 2016: CT Perfusion for Early Response Evaluation of Radiofrequency Ablation of Focal Liver Lesions: First Experience. Cardiovascular and Interventional Radiology: -

Kumra, V.K.; Singh, J., 1985: Drinking water supply in rural areas of Uttar Pradesh: problems and suggestive measures. The paper evaluates the problems associated with rural water supply in Uttar Pradesh. Problem villages are identified on the basis of water quality factors and distance to nearest water supply. The proportion of problem villages at the district le...

Arthur R.V.n Gool; Robert Verkerk; Durk Fekkes; Marjolein Bannink; Stefan Sleijfer; Wim H.J.K.uit; Bronno van der Holt; Simon Scharpé; Alexander M.M.E.germont; Gerrit Stoter; Michiel W.H.ngeveld, 2008: Neurotoxic and neuroprotective metabolites of kynurenine in patients with renal cell carcinoma treated with interferon- : Course and relationship with psychiatric status. Psychiatry and Clinical Neurosciences 62(5): 597-602

Klotman, M.E.; Henry, S.C.; Hamilton, J.D., 1987: Determinants of the source of cytomegalovirus in murine renal allograft recipients. Cytomegalovirus is present in a latent state in renal allografts and may be reactivated in recipients. While human and murine strains are alike in that a primary infection occurs in seronegative recipients of a kidney from a seropositive donor, th...

West, W.; Mcnary, H., 1956: An abstract of a study of the present and potential role of occupational therapy in rehabilitation. IV. American Journal of Occupational Therapy 10(4 Part 1): 150-6; Passim

Bo, O.; Raeder, M., 1976: Treatment of tibial shaft fractures by internal fixation and compression. Journal of the Oslo City Hospitals 26(6): 65-68