Abstract
A single injection of endotoxin (1 mg/kg, sc) in rats caused significant fever, body weight loss and reduction in gastrocnemius muscle mass, none of which was mimicked by pair-feeding. Infusion of endotoxin via osmotic minipump over five days caused transient fever and suppression of growth. Recovery of body weight was significantly enhanced by the administration of theβ 2-adrenoceptor agonist clenbuterol (added to the diet at 4 mg/kg). In a separate experiment, injections of endotoxin (day 0 and day 2) caused significant reductions in body weight gain (42%), mass (9%) and protein content (13%) of gastrocnemius muscle over 3 days. Addition of clenbuterol to the diet reversed all of these effects but did not alter food intake or the febrile response to endotoxin. Clenbuterol caused large (20%) increases in the ratio of RNA to protein in muscle indicating that it may have stimulated protein synthesis.β 2-adrenoceptor agonists may therefore be of value in preventingor inhibiting muscle atrophy associated with infection or injury.
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Choo, J.J., Horan, M.A., Little, R.A. et al. Muscle wasting associated with endotoxemia in the rat: Modification by theβ 2-adrenoceptor agonist clenbuterol. Biosci Rep 9, 615–621 (1989). https://doi.org/10.1007/BF01119805
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DOI: https://doi.org/10.1007/BF01119805