Biomaterial Database

Effects of glucocorticoids on motor units in cat hindlimb muscles. 1988

A J Robinson, and H P Clamann

Department of Physiology, Medical College of Virginia, Virginia Commonwealth University, Richmond.

The purpose of this study was to examine the effects of glucocorticoid treatment on the contractile, electrical and fatigue properties of isolated motor units of identified type. Although it is known that glucocorticoid administration induces atrophy and weakness most strongly in fast, pale muscles and to a lesser extent in red muscle, the relationship between steroid effects and motor unit type is not known. Properties of medial gastrocnemius (MG) and soleus (SOL) motor units were studied in normal cats and in cats treated with triamcinolone acetonide (3-4 mg/kg body weight for 10-16 days). Glucocorticoid treatment produced weakness preferentially in fast-twitch motor units. This suggests that catabolic steroids cause a reduction in the amount of contractile protein and hence contractile strength of motor units in inverse proportion to their relative activity or degree of use.

UI	MeSH Term	Description	Entries
D009046	Motor Neurons	Neurons which activate MUSCLE CELLS.	Neurons, Motor,Alpha Motorneurons,Motoneurons,Motor Neurons, Alpha,Neurons, Alpha Motor,Alpha Motor Neuron,Alpha Motor Neurons,Alpha Motorneuron,Motoneuron,Motor Neuron,Motor Neuron, Alpha,Motorneuron, Alpha,Motorneurons, Alpha,Neuron, Alpha Motor,Neuron, Motor
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D009124	Muscle Proteins	The protein constituents of muscle, the major ones being ACTINS and MYOSINS. More than a dozen accessory proteins exist including TROPONIN; TROPOMYOSIN; and DYSTROPHIN.	Muscle Protein,Protein, Muscle,Proteins, Muscle
D009469	Neuromuscular Junction	The synapse between a neuron and a muscle.	Myoneural Junction,Nerve-Muscle Preparation,Junction, Myoneural,Junction, Neuromuscular,Junctions, Myoneural,Junctions, Neuromuscular,Myoneural Junctions,Nerve Muscle Preparation,Nerve-Muscle Preparations,Neuromuscular Junctions,Preparation, Nerve-Muscle,Preparations, Nerve-Muscle
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D004576	Electromyography	Recording of the changes in electric potential of muscle by means of surface or needle electrodes.	Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies
D006614	Hindlimb	Either of two extremities of four-footed non-primate land animals. It usually consists of a FEMUR; TIBIA; and FIBULA; tarsals; METATARSALS; and TOES. (From Storer et al., General Zoology, 6th ed, p73)	Hindlimbs
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014222	Triamcinolone Acetonide	An esterified form of TRIAMCINOLONE. It is an anti-inflammatory glucocorticoid used topically in the treatment of various skin disorders. Intralesional, intramuscular, and intra-articular injections are also administered under certain conditions.	Azmacort,Cinonide,Kenacort A,Kenalog,Kenalog 40,Tricort-40,Acetonide, Triamcinolone,Tricort 40,Tricort40