Metabolic characteristics of skeletal muscle from lean and obese Zucker rats

Journal Article · · Growth; (United States)

OSTI ID:6029558

Campion, D R; Shapira, J F; Allen, C E; Hausman, G J; Martin, R J

The purpose of this study was to determine if the metabolic response to obesity and to pair feeding of obese Zucker rats to lean Zucker rats was similar across skeletal muscles. Oxidation of glucose, palmitate and isoleucine was studied in muscle strips in vitro using appropriate /sup 14 -/carbon substrates as tracers. The plantaris muscle was subjected to histochemical analyses using an alkaline actomyosin ATPase, NADH-tetrazolium reductase and an oil red 0 stain. Soleus muscles from both ad libitum and pair fed obese rats oxidized less glucose to CO/sub 2/, but released similar amounts of lactate when compared to the soleus muscles of lean rats. Oxidation of glucose was similar in the extensor digitorum longus (EDL) muscle of ad libitum fed obese rats, but lower when pair fed to the intake of lean rats. No differences were apparent in palmitate oxidation to CO/sub 2/ or in incorporation into lipid, except in the EDL muscle of pair-fed obese rats which exhibited a higher rate for palmitate metabolism when compared with lean rats. Isoleucine oxidation to CO/sub 2/ was higher in the EDL and plantaris muscles, but similar in the soleus muscle of ad libitum-fed obese rats when compared with lean rats. The magnitude of the difference in isoleucine oxidation was similar when the obese rats were pair fed. No differences in the percentage of plantaris muscle fibers sensitive to alkaline ATPase staining were observed. The plantaris muscle of obese rats, contained a higher proportion of oxidative fibers. These results indicate the great risk in generalizing about metabolic activity of the whole skeletal muscle mass based on observations made on one, or even two, distinct muscles in this animal model. Also, pair feeding of obese to lean Zucker rats did not result in uniform change sin metabolism between muscles of the obese rats.

• Research Organization: Richard B. Russell Research Center, Athens, GA (USA)
• OSTI ID: 6029558
• Journal Information: Growth; (United States), Journal Name: Growth; (United States) Vol. 51:4; ISSN GROWA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACID ANHYDRASES
ADIPOSE TISSUE
ALDEHYDES
AMINO ACIDS
ANIMAL TISSUES
ANIMALS
ATP-ASE
BIOLOGICAL MODELS
BODY
CARBOHYDRATES
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBOXYLIC ACIDS
CHALCOGENIDES
CONNECTIVE TISSUE
ENZYMES
GLUCOSE
HEXADECANOIC ACID
HEXOSES
HYDROLASES
IN VITRO
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LEUCINE
MAMMALS
METABOLISM
MONOCARBOXYLIC ACIDS
MONOSACCHARIDES
MUSCLES
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDES
OXIDOREDUCTASES
OXYGEN COMPOUNDS
PHOSPHOHYDROLASES
RATS
RODENTS
SACCHARIDES
TISSUES
TRACER TECHNIQUES
VERTEBRATES