caa a22 4500 388062193 CHVBK 20180307125124.0 cr unu---uuuuu 161130e199803 xx s 000 0 eng 10.1079/BJN19980047 doi S0007114598000488 pii (NATIONALLICENCE)cambridge-10.1079/BJN19980047 Effect of glucocorticoid excess on skeletal muscle and heart protein synthesis in adult and old rats [Elektronische Daten] This study was carried out to analyse glucocorticoid-induced muscle wasting and subsequent recovery in adult (6-8 months) and old (18-24 months) rats because the increased incidence of various disease states results in hypersecretion of glucocorticoids in ageing. Adult and old rats received dexamethasone in their drinking water for 5 or 6 d and were then allowed to recover for 3 or 7 d. As dexamethasone decreased food intake, all groups were pair-fed to dexamethasonetreated old rats (i.e. the group that had the lowest food intake). At the end of the treatment, adult and old rats showed significant increases in blood glucose and plasma insulin concentrations. This increase disappeared during the recovery period. Protein synthesis of different muscles was assessed in vivo by a flooding dose of [13C]valine injected subcutaneously 50 min before slaughter. Dexamethasone induced a significant decrease in protein synthesis in fast-twitch glycolytic and oxidative glycolytic muscles (gastrocnemius, tibialis anterior, extensor digitorum longus). The treatment affected mostly ribosomal efficiency. Adult dexamethasone-treated rats showed an increase in protein synthesis compared with their pair-fed controls during the recovery period whereas old rats did not. Dexamethasone also significantly decreased protein synthesis in the predominantly oxidative soleus muscle but only in old rats, and increased protein synthesis in the heart of adult but not of old rats. Thus, in skeletal muscle, the catabolic effect of dexamethasone is maintained or amplified during ageing whereas the anabolic effect in heart is depressed. These results are consistent with muscle atrophy occurring with ageing. Copyright © The Nutrition Society 1998 Ageing nationallicence Glucocorticoids nationallicence Muscle nationallicence Protein synthesis nationallicence Savary Isabelle Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France Debras Elisabeth Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France Dardevet Dominique Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France Sornet Claire Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France Capitan Pierre Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France Prugnaud Jacques Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France Mirand Philippe Patureau Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France Grizard Jean Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France British Journal of Nutrition Cambridge University Press 79/3(1998-03), 297-304 0007-1145 79:3<297 1998 79 BJN https://doi.org/10.1079/BJN19980047 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1079/BJN19980047 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Savary Isabelle Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France NATIONALLICENCE 700 1- Debras Elisabeth Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France NATIONALLICENCE 700 1- Dardevet Dominique Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France NATIONALLICENCE 700 1- Sornet Claire Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France NATIONALLICENCE 700 1- Capitan Pierre Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France NATIONALLICENCE 700 1- Prugnaud Jacques Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France NATIONALLICENCE 700 1- Mirand Philippe Patureau Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France NATIONALLICENCE 700 1- Grizard Jean Unité d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Recherches de Clermont-Ferrand Theix, 63122 Ceyrat, France NATIONALLICENCE 773 0- British Journal of Nutrition Cambridge University Press 79/3(1998-03), 297-304 0007-1145 79:3<297 1998 79 BJN CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge