HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Correspondence: Submit a response Alert me when this article is cited Alert me when Correspondence are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ørngreen, M. C. Articles by Vissing, J. Search for Related Content PubMed PubMed Citation Articles by Ørngreen, M. C. Articles by Vissing, J. Related Collections Metabolic disease (inherited) All Neuromuscular Disease Muscle disease

Exercise tolerance in carnitine palmitoyltransferase II deficiency with IV and oral glucose

From the Copenhagen Muscle Research Center and Department of Neurology (Drs. Olsen and Vissing, M.C. Ørngreen), National University Hospital, Rigshospitalet, Copenhagen, Denmark.

Address correspondence and reprint requests to Dr. John Vissing, Department of Neurology 2082, National University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100 Copenhagen, Denmark; e-mail: vissing{at}rh.dk

Background: Patients with carnitine palmitoyltransferase II (CPT II) deficiency often experience muscle pain and myoglobinuria during prolonged exercise because of impaired oxidation of long-chain fatty acids.

Objective: To investigate whether IV or oral glucose can improve exercise tolerance in CPT II deficiency.

Methods: Five patients with CPT II deficiency and healthy matched volunteers were investigated on a cycle ergometer at a constant workload of 60% of VO_2max. Perceived exertion, heart rate, and venous plasma glucose and insulin levels were monitored. The study was randomized, placebo controlled, single blind, and crossover. Glucose and placebo were administered both orally and IV in patients and IV in healthy subjects.

Results: In patients with CPT II, exercise duration was prolonged by 28 ± 8% (p = 0.02), and perceived exertion (p = 0.05) and heart rate (p = 0.09) were lowered by glucose infusion. In contrast, IV glucose resulted in higher heart rate during exercise in healthy subjects. Oral glucose and placebo resulted in the same exercise duration, perceived exertion, and heart rate in patients. Plasma glucose and insulin were consistently elevated during exercise by oral and IV glucose vs placebo, but plasma glucose was higher and insulin lower in IV vs oral glucose studies in patients (p = 0.02).

Conclusion: Exercise tolerance is markedly improved by a glucose infusion in patients with CPT II deficiency, but because of lower glucose availability and higher insulin levels that inhibit muscle glycogenolysis, the patients cannot achieve this effect themselves by oral glucose ingestion.

This article has been cited by other articles:

				T. D. Jeppesen, M. C. Orngreen, G. van Hall, R. G. Haller, and J. Vissing Fat Metabolism During Exercise in Patients With Mitochondrial Disease Arch Neurol, March 1, 2009; 66(3): 365 - 370. [Abstract] [Full Text] [PDF]

				M. C. Orngreen, H. J. Schelhaas, T. D. Jeppesen, H. O. Akman, R. A. Wevers, S. T. Andersen, H. J. ter Laak, O. P. van Diggelen, S. DiMauro, and J. Vissing Is muscle glycogenolysis impaired in X-linked phosphorylase b kinase deficiency? Neurology, May 13, 2008; 70(20): 1876 - 1882. [Abstract] [Full Text] [PDF]

				M. C. Orngreen, M. G. Norgaard, B.G.M. van Engelen, B. Vistisen, and J. Vissing EFFECTS OF IV GLUCOSE AND ORAL MEDIUM-CHAIN TRIGLYCERIDE IN PATIENTS WITH VLCAD DEFICIENCY Neurology, July 17, 2007; 69(3): 313 - 315. [Full Text] [PDF]

				J. Vissing and R. G. Haller The Effect of Oral Sucrose on Exercise Tolerance in Patients with McArdle's Disease N. Engl. J. Med., December 25, 2003; 349(26): 2503 - 2509. [Abstract] [Full Text] [PDF]

				M. C. Orngreen, R. Ejstrup, and J. Vissing Effect of diet on exercise tolerance in carnitine palmitoyltransferase II deficiency Neurology, August 26, 2003; 61(4): 559 - 561. [Abstract] [Full Text] [PDF]