Biomaterial Database

The effect of spinal cord transection on motor units in cat medial gastrocnemius muscles. 1984

R F Mayer, and R E Burke, and J Toop, and B Walmsley, and J A Hodgson

We studied the properties of whole medial gastrocnemius (MG) and soleus muscles, and of 74 individual MG motor units in three cats with long-term complete low thoracic spinal transection (TS). All animals remained paraplegic and there was considerable atrophy of MG and soleus muscles. Motor units in the MG pool were readily classified into the same groups, types FF, F(int), FR, and S, found in normal MG, but tetanic force outputs and mean fiber areas for the corresponding muscle fiber types were decreased in all unit types as were isometric twitch contraction times. The proportion of type F(int) motor units was greater (19.0%) than expected from normal samples (5.8%) and this was also true of the corresponding type 2AB muscle fibers (6.9% in TS vs 3.3% in controls). In addition, FR and S units were less numerous (17.5% each) than in control muscles (23.0% and 25.2%, respectively), and histochemical examination revealed a similar decrease in the percentage of type 2A (11.6%) and 1 (16.4%) fibers compared with controls (20.0% and 30.5%, respectively). The changes found in chronic paraplegic atrophy were different in some details from those found after chronic simple limb immobilization.

UI	MeSH Term	Description	Entries
D009043	Motor Activity	Body movements of a human or an animal as a behavioral phenomenon.	Activities, Motor,Activity, Motor,Motor Activities
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
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D009431	Neural Conduction	The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.	Nerve Conduction,Conduction, Nerve,Conduction, Neural,Conductions, Nerve,Conductions, Neural,Nerve Conductions,Neural Conductions
D010264	Paraplegia	Severe or complete loss of motor function in the lower extremities and lower portions of the trunk. This condition is most often associated with SPINAL CORD DISEASES, although BRAIN DISEASES; PERIPHERAL NERVOUS SYSTEM DISEASES; NEUROMUSCULAR DISEASES; and MUSCULAR DISEASES may also cause bilateral leg weakness.	Paralysis, Lower Extremities,Paraplegia, Spastic,Spastic Paraplegia,Paralysis, Legs,Paralysis, Lower Limbs,Paraplegia, Ataxic,Paraplegia, Cerebral,Paraplegia, Flaccid,Paraplegia, Spinal,Ataxic Paraplegia,Ataxic Paraplegias,Cerebral Paraplegia,Cerebral Paraplegias,Flaccid Paraplegia,Flaccid Paraplegias,Paraplegias,Paraplegias, Ataxic,Paraplegias, Cerebral,Paraplegias, Flaccid,Paraplegias, Spastic,Paraplegias, Spinal,Spastic Paraplegias,Spinal Paraplegia,Spinal Paraplegias
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
D004594	Electrophysiology	The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
D005260	Female		Females
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
D006651	Histocytochemistry	Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.	Cytochemistry